Ask HN: How do I teach myself design?

I've advanced enough just by looking and trying to understand what makes other sites so appealing.

But I feel that I am at an impasse. I have no training at all in color-theory, design, or anything like this. The learning process is so different from what I'm used to, I think.

If I need to know how to do something in an API, I look it up. If I'm new to a language, I read a book.

I understand that just doing it over and over is pretty much the process for anything, but I feel that I could use some refinement now, rather than later.