I haven't really played with it (although I sometimes make my own simple patterns, frankensteining the ones I have already), I LOVE this book. LOVE IT. It's very simple, and very, very thorough.

http://store.doverpublications.com/0486452549.html

If you're going to start playing with patterns, start hoarding old sheets. They make fine trial garments and they're cheaper than muslin. Also if you tell people you'll take old woven sheets (not knits) you'll get stacks.

H