Updated: Aug 13 2012
EVEN MOAR SKIN SWATCHES!
The best way to improve is to draw from real life. That's the best way to learn. If you don't know how to draw a certain angle of a hand or an arm, you shouldn't fudge it, you should always look it up and figure out how to draw it right. Hiding the hands behind the body is a no-no, people! The proof of bsing is easy to see: http://neofox.deviantart.com/journal/ART-knowledge-is-power-282518336
But often it's very hard to weed through the crap to find good stock to use as reference. So here I am, doing the work for you and naming some helpful resources.
I've been teaching my friend Kitteh how to draw, so I'm learning first hand just what steps to take to improve.
There's one very special thing you must do to improve. With this special thing you can go from amateur to pro. And that's PRACTICE. You can get all the references and tutorials you want, buy all the books, save all the tutorials and referenc