So, you've considered your past experiences and your motivations, and you've got a decent idea of the effort required of you: Six to eight hours of solid work before you start showing improvement, and about twenty hours total before you start to exhaust the low hanging fruit. You want to learn to draw. What exactly does that entail?
A lot of things, really. There's probably hundreds of subskills, techniques and bits of knowledge that go into creating a quality drawing. But I think they cluster into three main categories:
- Technical Skill
- "Instilling Energy and Weight"
Each of these skills is developed with different exercises, requiring different mindsets. Switching between those exercises can be difficult. Studying any of them can produce something that is interesting to look at, but ultimately you want to integrate them into a single, fluid mental process. You'll need to develop some competence in each of them first. As you begin, the most important thing to remember is that *learning* to draw is not the same as actually drawing. To improve as quickly as possible you may have to set aside the reasons you wanted to draw in the first place. Don't worry - you'll achieve those terminal goals in time.
In this article I'll briefly discuss each of those skill clusters, and how I believe they relate to rationality.
The ability to see reality, as it truly is. "Reality" refers both to the physical objects and light that you're looking at, as well as to your perception of your own mental processes and how they should be interpreting those physical objects. If you have previous rationality training, this is where I expect it to benefit you the most. Your model of reality will be flawed, and you'll need to fix it. Existing ability to notice biases and counter them should give you an advantage.
The advantage *may* come in reduced study time (I'd need a lot of data to confirm this) but mostly of the advantage will come from willingness to actually study effectively in the first place (this is a genuinely big deal). With minimal instruction, you could probably figure out where your biases lie and how to fix them. Some knowledge of cognitive science might even give you insight as to where and why they might be flawed. I'd be interested if someone without much drawing experience attempted to predict their biases in advance, once before having drawn at all in the recent past, and once again after one or two drawings.
It would still take a long time to do that, which is why in the next article I'm going to give away a lot of common answers. As a bonus rationality exercise you may want to predict those answers in advance. (For the benefit of others, leave your answers encrypted in the comments)
I'm not sure how to test for it, but I believe the skills here can transfer to other domains, if one deliberately made the attempt.
The ability to control your pencil, moving it in the direction you want it to go, applying different amounts of pressure to make it darker or lighter, thicker or thinner. As your observation and technical skill improve together, you'll learn to identify important parts of reality, and use pencil techniques to emphasize them properly. It's important to develop a minimal threshold of technical skill. But afterwards, it can wait until you've gotten a solid understanding of Observation, Energy and Weight.
Nine thousand hours practicing technical skill is what makes the difference between a competent amateur and a professional. A few of those hours will yield low hanging fruit, but not many. Rationality won't be particularly relevant here. I'll be doing one article that covers the basics, and later on I'll link some online tutorials that may be useful *after* you've put in an initial twenty hours or so.
Instilling Energy and Weight
This is the most mysterious of the skill clusters. It's (fairly) obvious to a lay person that they need to look at things and practice moving their pencil in order to improve at drawing. That's what high school art students focus on. But their drawings feel flat, and lifeless. They'll copy something from a photo and there won't be anything obviously wrong. It's just... boring somehow.
The problem was that the technical skill they developed focused on small, slow, precise movements. To instill energy and weight, you need to be able to draw big, bold lines, and to draw them quickly. They require a kind of hand-eye coordination (and more importantly, arm-eye coordination) that you've probably never developed. The first big, bold lines you draw will look hopelessly wrong against reality. You need to keep practicing, until your entire arm can do what your brain wants it to. Until then, much of the technical skill you acquire won't be implemented correctly.
The harder part is the that to instill energy and weight, you may sometimes need to NOT draw the reality you see. As this skill develops alongside technical knowledge, kinesthetic skill and observational ability, you'll learn how to draw lines that differ from reality to make your drawing more interesting and creative, without sacrificing a realistic look that captures the original likeness. And you'll need to start doing this with a part of your brain so small and underdeveloped that it doesn't even show up on your model of yourself.
Your rationality training will probably not help you, because it doesn't directly prepare for this sort of thing. The actual skills you're developing here are kinesthetic, not high level cognition. But I think preparing for this sort of thing is a kind of instrumental rationality technique we *should* be working on. This weirdness you feel as you practice, the certainty that your teacher is screwing with you and that you should go back to the comfortable ways you're familiar with... this is the feeling of your model being _wrong_, and butting up uncomfortably against reality of how your brain works. Not just getting a fact wrong. Not even failing to ask the right questions in the first place, but lacking the sense capabilities needed to even interact with the part of reality you needed to see in order to ask those questions. It's having your decision-making algorithm *be* wrong on a gut level that can't really be explained, only experienced.
I think this is among the more important experiences that drawing offers, if the effort is made to understand it. Obviously, not every "wrong" feeling you ever have will stem from a model-reality mismatch. Sometimes when something feels wrong, it really is wrong. "Wrong" feelings are still evidence. But they are not absolute evidence.
Yes, I know you already "knew" that. But unless you've already had a similar experience, you probably didn't really understand it on a gut level. Being able to recognize when you're approaching things is a fundamentally wrong way, and be okay with it, is an incredibly important skill. And because each way of being fundamentally wrong is slightly different, we could use a variety of examples in order to better understand new ones in the future.
Existing Less Wrong literature has two areas that I consider to have helped build this skill for me. One was the overall "woah" moment when I realized I should actually incorporate the Singularity into my model of the world (Even this doesn't really count, because the "that can't possibly be right" feeling was accompanied by "it would be sooo cooool if it were!" instead of "ugh this is painful to think about). The other was the emphasis that quantum physics isn't weird, YOU are. Those realizations may have more serious consequences on how I interpret the world, but the experiences themselves were weird on a similar level. Plenty of other content here talks about this sort of thing, but there's a limited number of ways to actually experience being wrong in this way. I think we need more of that.
Somewhere in your brain is an invisible mental-muscle that you never knew existed. You'll need to trust that it exists, and start practicing with it. Eventually you'll be able to "see" that part of your mind, and you'll incorporate it into your model of yourself.
And then you can learn how to make interesting depictions of reality.
Perhaps more importantly, you can learn to create Art™.
 Many readers may notice that this statement... really makes no sense. That's because it's a simplification. I'll explain the more complex rule that actually governs it in a later post. Feel free to speculate in the comments about why I chose to simplify it that way.
 I know that's three posts in a row where I hint at the same mysterious thing. I'm building it up because it's important and needs to be emphasized. You're still not going to really understand it until a teacher makes you do it and helps explain some kinesthetic things that I'm going to have a hard time communicating through written text. Three posts from now I'll attempt to explain it well enough that you'll understand the teacher the first or second time e explains it, rather then after many frustrating hours.
 I do NOT recommend people learn to draw purely to experience this feeling of wrongness. In order for any of this to work you need to be instrinsically motivated.
 This may technically be untrue, if you HAVE already become aware of this mental-muscle and used it in some fashion. It may not even strike you as an odd thing, if you've had it for a while. But I'm willing to bet it'll be a new thing for most people here. I actually think we'll have a higher percentage of people who have a particularly hard time working with it.