kip/bot/blog

When I was learning to program in C/C++, for several days/weeks and on several attempts I hit the pointers plateau — that thing which, conceptually, I couldn’t get my head around sufficiently to really grok the damn things. I eventually took a class that spent three weeks on it and now I understand them — their purpose, their usage, their style and how to troubleshoot them. A couple summers ago, I took a geek vacation between jobs and worked my way through the NYU ITP Physical Computing class curriculum and dug deeper into some Arduino stuff.

After a couple weeks, I hit a plateau. I needed things like shift registers to multiply the number of LEDs I could manage with the Arduino’s 13 pins; I needed to use a 555 timer chip to get pulsing, and there was a whole range of chips starting named 74______ that were described as “hugely useful” or “workhorses”. These things were critical and basic, like pointers, but (like pointers) it was impossible to find documentation for them that was comprehensible to someone with my level of experience. It was one of the weird places where the web let me down. I must have done dozens of searches, asked everyone I could for help, and could find nothing. Which is a drag, cuz those chips are what give real ooomph to physical computing projects.

Make Magazine has fixed that with Make: Electronics, an unusually good book even by O’Reilly standards. It contains in-depth explanations of how transistors and logic gates work at the physical level — giving you a more intuitive sense of how to work with them (rather than following steps by rote); detailed descriptions of the pins at three levels: the official specs, the occasional nomenclature, and the actual function; and some simple circuits that show what the thing does. The last might be the most important. Even the most basic 555 Timer chip examples I could find had so much stuff going on that it was impossible to isolate the chip and learn, iteratively through tweaking the code, what the things does. To top it off, the Maker Shed Store has a components kit that pulls all the stuff (including jumper wires) together for you.

The one weird thing about the book is in the index:

What the hell kind of alphabetization system is this?

Of course, it’s not like I have time to do anything on my nifty hand-made workbench. But it’s nice to have it when I’m ready. Hope springs eternal. Put differently.

while (!endOfUniverse)
hope.spring();
;

Ha!

GS&P just put out a gorgeous and inviting teaser/trailer for the Adobe Museum of Digital Media. It’s a beautiful, well executed virtual museum. The creatives have done some interesting things around conceiving of a virtual building that could live in any real city (or virtual rendering of a real city), and how to move about and recreate the sense of sight lines and movement of a real place.

The whole exercise is a preview, so it’s hard to know what we’ll be seeing in August, but I tend to be pretty meh about virtual anything. It seems like an easy impulse that we’ve lived with for many years: put the word virtual in front of anything and you have a concept for digital, along with a baseline for solving most of your design problems.

I did a talk last weekend to museum and art publishers about where e-Readers and interactive reading were going. To prep for the talk, I grabbed a bunch of art books for the iPad. In general, the results were far from magical. The interactions were banal, click and play kind of stuff. But, one of the books that horrified me was “The Art Authority”:

Seeing this screen gave me flashbacks to early CD-ROM designs and BOB from Microsoft. Back then, we used metaphors and virtualizations because, I think, computers were new to people and we wanted them to feel comfortable and grounded. To do that, we tried to give them a sense of physicality.

There are all sorts of problems with physicality in designing interactive/digital/screen-based experiences: 1) you use a lot of real estate for the interface-metaphor and therefore less space for the content; 2) the interface-metaphor behaves in an insistent way, continually making itself the center of attention, rather than fading back into the role of facilitator/quiet mediator of content; 3) interface-matephors pull you into a level of specificity that can actually break rather than create an illusion of physicality. As a result, most of them are cheesy or childish.

To be clear, GS&P have gone farther and built something virtually that would be impossible in the real world. Already, we’re in the realm, then of speculative architecture rather than simple virtual thinking. And, as I mentioned above, the experience is beautiful and the space is interesting, so the speculative architecture aspect of the project is quite teh awesum.

But despite the coolness of the building, there’s still a need to justify the overhead of the interface-metaphor. In the physical world, you need a physical museum to show art. That physical world has requirements that make museums great architecture: the environment to protect the art, how crowds are managed, what the space for art encounters is like, what kind of art can be shown, what the building says about the art within, what an art viewing session is like, and what the building does for the viewer as a piece of art itself.

The internet is already a ‘place’ where art is displayed. So, what do we get out of putting a virtual building in between the internet and the art that would normally live there? And is it worth the costs of the overhead (especially if people are viewing it on an iPad or something smaller)?

The part that’s really interesting to me, is the way the video for the interviews was handled. There’s a satellite transmission aspect to the video, the purpose of which is unclear:

If I ventured to guess, I would say the idea was to stylistically degrade the reality of the real talking heads to dial up the reality of the virtual building. But that graininess goes away when the trailer shows team meetings, so I can’t be sure. Leaving aside the motivation, however, the degraded scan lines do highlight, even or create discomfort with the larger metaphor by once again calling attention to what’s being done rather than than the art that will, eventually, be displayed.

In a real museum (or I should say a Real Life Museum), the trailer would be about how the curators and the museums conceived of the show — how did we choose the themes and the art, what popular and academic understandings of the artists did we want to explore or explode, how did we arrive at the final works, what collaborations and personalities came to bear on the final product — not how the space was conceived.

Enough. Twitter version:

When we do virtual things, we need to ask, what’s the star of the show, what’s the point, is there balance, and are we serving the content?

After my TEDx Kent talk — a delightful romp though kipbot’s pissiness at how kids today don’t respect the amount of craft and expertise needed to do digital — someone recommended I read Rethinking Expertise, by Harry Collins and Robert Evans. Collins and Evans are sociologists at Cardiff University who specialize in the acquisition and social understanding of knowledge and expertise. The book is

meant to increase the chance that the process of coming to be called an expert will have more to do with the possession of real and substantive expertise … to treat it as something other than relational

It’s quite a good read, though the introduction, and the purpose is kind of sad: “First we need to work out what it means to know what you are talking about.” What a sad task to have to take on.

There is a lot in this book to blog about, and I haven’t finished reading it yet, but I had an aha! on the subway (the realization and insight kind, not the marketing kind). The book is based on a ‘periodic table of expertises’, which contains a spectrum of knowledge levels around which we build our expertise. The spectrum reads:

beer mat knowledge - little trivia fun facts that are technically right, but doesn’t get you beyond definitions
popular understanding - such as a pop science book that gives you enough to talk about it at parties, but not enough to answer questions
primary source knowledge - reading books in the field
interactional expertise - doing it
contributory expertise - originating ideas in the field, serving as part of the peer community that defines and propels it

The last two are the areas of true expertise - people who study a field by immersing themselves in the primary literature (often in university) and then do the field, where they gain deeper knowledge and understanding, eventually moving into a kind of mastery where they shape the field with their contributions. The book is focused on science, so the idea can be understood, by majoring in biology, going to grad school where you study more primary literature, but are in a lab and teaching (interactional), and then doing some research that can be published as a contribution to the field (the dissertation).

Anyway, I love the beer mat analogy, and it’s actually real — they found a beer mat for Babycham company that tells you what a hologram is (with exclamation points too!). But the real insight for me was the faultline between primary source and interactional expertise. How many times have we made ourselves conversant in (and considered ourselves capable of managing) a field after reading a couple books in the field? Without doing the work, without reading something by or talking to someone who actually has done the work to see what the difference between dynamic interactional and static written knowledge would be. The degree of immersion is important here. In his reportage and non-fiction writing, Martin Amis regularly refers to reading a couple yards of books to get a handle on the field (specifically he was talking about nuclear disarmament policy and Stalin research). This was a huge insight for me as a manager and as an observer of other managerial cultures.

The other piece I really liked was the distinction around popular literature on a field. Somewhere between beer mats and text books are popularizations — the Stephen Hawking pop science stuff. I used to make fun of the Business Week cover dynamic in the internet industry — the day something gets covered in BW, the client or your boss calls and says “OMG we need to have this!!!!” But now, looking at the broader spectrum of expertise — going from beer mats out to doing and originating — I’m wondering if things like our beloved HBR, the sacred text to many of us (including me), is actually popular or primary.

PS Jeff Parks, in his talk, “Being Human is not Quantifiable” has a funny riff about expertise. While looking at Malcolm Gladwell’s 10,000 hours quote, he gently mocks the notion of a social media expert arguing that this stuff hasn’t been around long enough for some to put 10,000 hours into it!

I have a weird memory from a surfer movie. I can’t remember the title, and having never watched surfer movies aside from stopping briefly on the remote in between stops, I have no context for it. (Major exception to the previous sentences: Point Break, which, of course, transcends and resists genre classification.) So here’s the memory:

Some girl, wearing an old-fashioned, square cut bikini is talking to an older guy about her boyfriend-the-hero-of-this-movie’s chances at winning a surfing contest. The boyfriend is, of course, the underdog. He has been screwed by his wealthier, more practiced, less scrupulous, and prettier but less attractive opponents. The boyfriend is behind and his success depends on the next run. The girlfriend wonders what’s needed to pull off this surfing and life miracle.

The older guy is big, barrel-chested, chomping a cigar, wearing a tank top and hat and holding his binoculars. He looks pensive and says something like “well, he may have the skill, and he may catch a good wave, but he needs more than that . . . he needs a great, big chest full of character.” (Not sure how to spell chest full — chestful seems like treasure chest. Chest full feels too biological and ribcage focused.)

This kind of thinking is common to people and companies new to interactive work. There’s a belief that spirit and energy and character can overcome all obstacles, even the laws of physics or ignorance (or a bad wave). In the movies, we see repeatedly how someone can overcome absurd adversity with a pep talk, digging down and finding the fire, or coming up with a clever trick (that Karate Kid broken ankle thing). In the Olympics, many of the events give athletes three shots at getting it right, so that third attempt is a chance at making up for a suboptimal performance and bringing a lot of heart to win the gold. In distance events or timed sports, there’s always a hope that the runner can pour it on in the last five minutes, or the team can put together a series of scoring drives (touchdown!, on-sides kick!, touchdown!, interception!, gadget play! touchdown! ZOMG we won!).

But interactive isn’t like that. Notions of heart, digging deep, fishing something out of your bag of tricks doesn’t work. You’re usually up against laws of physics. As Fred Brooks reminds us, nine women in a month can’t make a baby — no matter how much character they have.

Interactive is like chess. It’s built on a foundation, there are virtually no clever tricks, no ways to surge and overcome a bad position. If you play a poor opening, your middlegame options are limited — you’re on the defensive. If your middlegame position is weak, you can’t go on the attack, even if you have a lot of heart for it. If your endgame is technically lost, all you can hope is that your opponent makes a mistake. But no pep talk or chirpy can-doism can change the fact that you have a lost position. You need to play to win from the beginning, you need to begin with a view of the end, you need to be in the now and be in the future calculating possible nows that may arise.

For my software surfer movie, some gems:

Measure twice, cut once.

Have a plan.

Explore the implications of your moves.

When you have a problem and hear someone say “oh, it’ll be fine, I’m not worried” a half tone higher than their usual voice, smack that person on the forehead until s/he starts worrying.

Track your projects early, not just two weeks out from launch.

In fact, don’t bother checking in two weeks out from launch, cuz if it’s broke it’s too late and you’re only gonna screw it up.

Don’t trust the happy optimists, fill your team with people who like solving puzzles and loathe inelegance and easy solutions.

Most important, keep your head in the game, look at the whole board, and calculate.

The celebration of failure has become a tired, counterproductive meme.

Sure, the tension involved in celebrating something normally thought to be bad gets your attention. It’s also a way to get people out of their comfort zone. So cheers for that.

But, really, we actually want to succeed and the more I read about failing forward, failing your way to success, and not being able to succeed without failing, the more I think the word does us a disservice on several levels. For starters, failure, it’s important to remember, is a broad umbrella. On the positive side, the one that’s worthy of fetishizing, it includes things that happened not to work. They didn’t fail so much as the client didn’t buy it, the market wasn’t ready for it, it was ahead of its time, or it was a good idea but not popular enough to be profitable. On the negative, however, failure also includes (and originally meant) screw-ups, incompetence, miscalculations, and arrogant dilettantism masquerading as expertise.

The problem is that the word failure doesn’t contain within it the means for evaluating good ones and bad ones. Failure doesn’t have an internal quality metric in its meaning that helps us identify the ones that actually advance the work and ones that should result in heads being knocked, going back to the drawing board, hitting the books, or putting together a new team.

Celebrating failure doesn’t help us increase our likelihood of doing quality work so much as it increases our chances of stumbling into it. By celebrating failure, we encourage peolpe and teams to try more, and more risky, ideas. But we don’t encourage people to focus on craft, execution, or a notion of quality. For some cultures, this might be good. If you’re in an environment that is so stale and idea-less that no one ever goes beyond the obvious, than you may need that jolt. But, in an environment that is already supposed to be about creativity, innovation, and design, you’re probably dumbing the place down. By talking about failure, rather than iteration and revving, we’re not advancing design thinking so much as inflating attitude. The word failure doesn’t have enough oomph in it to get people thinking.

Worst of all, I think, celebrating failure gives teams and people easy outs when something doesn’t go well. Since failure doesn’t contain a quality metric we have trouble describing what constitutes a useful failure. Most conversations about failure assume that everyone knows the actual complete screw-ups (do we really?) but don’t help identify the earnest, but ultimately wasteful, failures. As a result, when we fail, it’s easy to describe one’s self as taking a shot and missing but then celebrate the taking of the shot anyway. Rather than critique something to find out what the hell went wrong or, more productively, what do we do better, celebrating a failure implies that things were fine, it just didn’t work out.

To be clear, I think we should promote the taking of risks. I absolutely believe that the quality of an idea — its originality, elegance, or efficiency in solving a problem or doing something new and wonderful — should be celebrated even if the product ultimately doesn’t succeed in the marketplace or isn’t approved by the client. (I also think it would be an interesting exercise to see if celebrants of failure in the design world are willing to go so far as to call the Segway, Zune, and the XO successful failures.) But I think we should celebrate failure in a very different way: by calling it iteration, critique and refinement. Better yet, let’s call it experiment.

Experimentation is a much better word to use, though I already know it’s too wonky and beaker-y to catch on. Still, it’s worth talking about the difference if only to make the word we’ll be stuck with for the next year — FAILURE! — meaningful. Here’s the difference:

Let’s use a fresh example from an unexpected place: the iPhone. This is from the WIRED cover story:

It was a late morning in the fall of 2006. Almost a year earlier, Steve Jobs had tasked about 200 of Apple’s top engineers with creating the iPhone. Yet here, in Apple’s boardroom, it was clear that the prototype was still a disaster. It wasn’t just buggy, it flat-out didn’t work. The phone dropped calls constantly, the battery stopped charging before it was full, data and applications routinely became corrupted and unusable. The list of problems seemed endless. At the end of the demo, Jobs fixed the dozen or so people in the room with a level stare and said, “We don’t have a product yet.”

The effect was even more terrifying than one of Jobs’ trademark tantrums. When the Apple chief screamed at his staff, it was scary but familiar. This time, his relative calm was unnerving. “It was one of the few times at Apple when I got a chill,” says someone who was in the meeting

Jobs rather famously doesn’t celebrate failure. What he’s done in this moment is call something what it is — inadequate, not acceptable, deeply troubling. At the same time, however, he didn’t throw a tantrum. There was a critique in his assessment of the prototype/iteration/rev/version/experiment/failure — and it went beyond the bugs. Bugs can be solved and closed, the bigger issue was that it wasn’t coming together as a coherent product. That was a design moment, an experiment being evaluated — there was no celebration of failure.

As Nick Cage so memorably re-told the story in the immortal national treasure National Treasure: “When Thomas Edison was asked how it felt to fail 99 times trying to invent the light bulb, Edison said ‘I didn’t fail 99 times. I discovered 99 ways how NOT to make a light bulb.’”

Stop failing and patting yourself on the back for it. Start experimenting and stay focused on quality and success.

Oikos (οἴκος) meaning “House + Nemein (νέμω) meaning “To manage”

One of the things the iPad debate is missing is consideration of household and customer decision-making. Many of the conversations out there ask legitimate questions about whether the iPad meets real needs well. Other conversations have legitimate points about how it’s an important step in improving human computer interactions even if the need isn’t clear. What’s missing, and I think this is an interesting design discussion, is how people make high consideration purchases.

One of the biggest mistakes in the discussion is likening the iPad to the iPhone or iPod. Both the iPhone and the iPod were entries into well-established categories — mobile phones and portable music (I’m thinking Walkmans here, not MP3 players). Both categories had known pain points. For the phone there were crappy interfaces, the number pad as input device, and for me the miserable voice mail systems. For the music players there was the tradeoff between how many songs you had with you and how heavy/cluttered your bag would be (Walkman and Discman), or what a pain in the neck it was to get music onto your MP3 player. Apple walked into a known category which was serving known needs poorly and addressed pain points within it. For consumers already inclined to spend their money in this space, Apple’s premium price point wasn’t a problem — and millions gladly paid for the superior product.

The iPad purchase decision, however, happens in a different space - One in which people aren’t already spending money in the category to meet their need or where they are meeting their needs in other ways that don’t particularly suck. The not particularly sucking is important:

- books and eReaders work fairly well
- game consoles and portable game devices work extremely well (I’m gonna ignore the various rings of death on the XBox)
- people have TVs and iTouches for watching stuff and they work well

(Netbooks kind of suck and web browsing on a laptop often sucks, so Apple has an insight there, though it’s not clear that the iPad is really a tablet or netbook competitor.)

This is a pretty weak set of impulses to buy a high-price device. The urgency for the purchase of the iPad is much less than the iPod (I need to have my tunes in my bag! at the gym, in the car, at the office!) or the iPhone (I hate my phone; I don’t want to carry an iPod, a camera, and a phone). Lots of momentum and lots of day-to-day justification to drop some real coin in the phone and music player category . . . but where’s the energy for a mass audience on the iPad? I don’t see it — changing the way we compute is pretty tepid for something that’s more than half a thousand dollars — with which you can buy an XBox and best-selling titles, a good digital camera, a good netbook, a flat screen tv in the bedroom. It’s also a nice sum not to spend at all.

Put this decision in the context of a semi-affluent, or non-affluent household. Think of a family where money decisions of this size are made by two people and against larger issues like mortgages, tuition, college savings, car payments, etc. That person is spending $500 for . . . what?

Add to that, the number of devices already present in someone’s home:

- a flat screen TV
- a gaming console (that may be netflix-enabled)
- a desktop computer and/or a laptop
- a mobile phone and/or an iPod touch
- a DVD player that plays Hi-Def and may be netflix enabled

Hard to see how this conversation ends in a purchase: Honey, I want something for games that are bigger than my DS, but not as big as my TV. Darling, lets drop $500 so we can watch TV in bed on this thing (which I’ll need to buy a stand for) instead of the laptop or the TV. But sweetie, I need a bigger media screen for movies on the subway, my Touch doesn’t cut it.

In grad school, I loved when Robert Heilbroner would remind people of the origins of the word economics — household management. Managing the household is something we still do, but as marketers or product designers we tend to ignore the larger household in which a purchase decision is made (at least those marketers or product designers participating in the iPad frenzy). I think it’s an interesting design question and might make me feel less small-minded as I repeat that the iPad will sell well as a web appliance, but it won’t be much bigger than the Apple TV.

I continue to be crotchety about generalism and the speed with which people think they can learn to be something (see crotchety posts here, here, and here. Here too. Oh, and here. God, do I ever stop? Well, no, but this one here isn’t grumpy.). Listening to Studio 360’s podcast about Moby-Dick today (while I was engaged in the years-long journey of becoming a better cook — in this moment by trying to improve my chicken stock and mushroom barley soup), there was a surprisingly great interview with Ray Bradbury. Why surprising? First, because, despite my love of SF and other genre fiction, I tend not to expect profundity from SF writers. Second, having never read Bradbury, I assumed whatever acclaim he gets is because of the ideas behind and the clever titling of Fahrenheit 451, not for any skill as a writer. (I need to make that right and at least buy, if not actually read, something of his on my Kindle.) Third, it’s just such a nice way of putting something I and the voices in my head are often on about that my head snapped up and I almost cut off the tip of my left index finger when he said it.

Anyway, I spend lots of time trying to convince people to respect craft and the time it takes and the value behind going deep in subject areas. But I see lots of people assuming they’re experts in things after they’ve done something once, or read a couple articles and books about it, or memorized a couple catchy phrases. Malcolm Gladwell recently helped highlight the fallacy that conversancy == expertise or that once is enough to be a guru when he highlighted the thinking that indicates you need 10,000 hours to get really good at something. But that factoid alone doesn’t quite get it across, because it’s not 10,000 accretive hours only that get you there. It’s 10,000 accretive and repetitive hours, with an emphasis on repetitive — you don’t learn new things so much as you learn more about the richness of the things you know. Describing this process and helping people understand it is challenging.

So, Bradbury wrote the screenplay/adaptation for the Gregory Peck film version of Moby Dick. (I didn’t know that, so already I’m happily smarter as I chop my leeks — working on getting more rhythm and precision and speed with my 8″ knife.) He apparently rather famously talked about being Herman Melville for a day during the writing of the screenplay and the Studio 360 host asked him to explain the why and the how of that:

what you try to do is get it into your bloodstream, get it into your unconscious. You can’t intellectualize it, that won’t work. But if you read a book 80 or 90 times, which I did, some sections I read 120 times, and you put that all into your bloodstream . . . and then you ignore it and let it come to the surface, emotionally, passionately . . . then you become the chaser and chased.

I like the image of getting it into you bloodstream and waiting for it to surface. Even more, though, I like the idea of ignoring the material and letting it sit in your unconscious.

I’m starting to look for a piano teacher (my previous teacher has, alas, moved to the west coast. A moment’s homage to her: she was awesome, played my piano beautifully when she walked me through Mozart sonatas and had a fun mix of stern teacher (reflexively pushing my elbows up and straightening my back) and music lover (listening to any vague musical connection I made between a theory assignment and something I was listening to.

So, a teacher I’m looking at has all sorts of things to love, chief among them his professional/academic work around Mahler. But he has a section on his site called Why study music? which highlights some of the benefits of taking a craft seriously and going deep into something. His key reasons, paraphrased below:

Dealing with pressure — the site refers to children learning to deal with pressure, but there’s something impressive for adults to, on a weekly basis, confront a piece of music that doesn’t come easily to them. Knowing that a lesson is coming up is just enough pressure to force you to take a longer view, break the piece down and work on it. It’s also long enough to be rewarding when, by the end of the week, you being to master it.

Responding to Criticism — I’m surprised how many design focused places don’t ‘workshop’ things and how many times we hold back from really working over a piece of work. One of the key, but most frequently overlooked, tenets of design thinking should be/is iteration and revision. While anyone’s first rev should be excellent, it should be understood that further revs will only improve the final product. Even if you come back to the original design, you’ll have a stronger, more confident understanding of it.

Persistence — in my world of marketing and interactive, there’s a borderline obsessive interest in the next thing, newness, novelty and never seen before. Sitting with someone for a while, working on something for longer than a quarter, doing a truly better v2.0 that is continuous with the previous version is not only hard to do, but often scorned. That said, however, there are a lot of creative types in the field who know when to dig in and fight the good fight or keep on pushing to validate an idea.

Multi-leveled focus - inset Steve Jobs quote about zooming in and zooming out and the design trope of ‘rinse and repeat’.

Project management - taking a long view of mastering a craft or something within the craft requires some PM like thinking. For a piano piece, my instructors regularly tell me how to break it down: “start with the left hand until it feels smooth and you find some melody in it, then focus on the melody right hand only, and work on the middle section until it feels clean, then you can add the intro, do dynamics last.”

The bolded names of the benefit are his, the interpretation mine. His page about why we should study music is pretty nice read, highlighting brain age as well as craft/life lesson benefits . . . and, oh yeah, the joy of playing music you love!

Perhaps is because I’m getting old. Perhaps it’s because, having gone through 2.5 career changes and paid my dues/been schooled 2.5 times. Perhaps I’m wrong, but I found this Zen Habits article about
how to become amazingly great at something refreshing. I’ve been to so many places where people are going to “get digital” in 3 months, or pick up a new competency through a couple hires, or “spend a weekend” with something to plumb its depth and master its rhythms. I loved the setup to this article:

Very often you’ll see blog posts or books teaching you to “master” a skill in only 10 days, or 3 days … in fact, it used to be 30 days but the time frame to master something seems to be shrinking rapidly.

I’ve even seen tutorials claiming to teach a skill in just a few hours. Pretty soon we’ll be demanding to know how to do something in seconds.

Instant mastery of skills and knowledge! Hey presto!

Unfortunately, the reality is something a little less magical. Or maybe that’s a fortunate thing.

I love this Instructable and wish I could do it for me. The author, responding to that clear-but-squishy-edged school of thought that various stimuli are good for infants, created a remote-controlled pattern of fiber optic lights in his soon-to-be-born baby’s ceiling. He can remotely control the overall brightness, the rate of twinkling, and the phases of the moon (waxing and waning):

Full lesson at Instructables