The Cornell system is pretty famous note-taking method. I also saw while checking for the Wikipedia page for that, there's a partial wikibook on Note-Taking with some various tips and links, and a Note-Taking article that outlines several methods.

But my advice would be not to stress too much about how you're taking notes. Writing helps with memory, but from what I can tell it's really the act of taking the information, choosing what to write down and how to re-word it that does the heavy lifting.

So basically, just do it, even though it's imperfectly. Sit down to learn something, and as you read, watch, or practice, decide what's important and jot down something on your paper that you think captures the idea.

Also be wary of the trap of buying nice pens and notebooks. That stuff is cool if it motivates you to actually start taking notes, but can drag you down if you let yourself get too particular about it.