The team behind Freakangels have provided us with an incredible how-to: http://www.freakangels.com/?p=98 Mostly, because it's so concisely written while at the same time covering aspects of efficiency, accuracy and work flow. While reading it, I wouldn't focus too much on the idea of putting the lines layer on top set to multiply, as there are at least two other ways of doing that kind of thing that I use to virtually the same effect. It's good advice, but there are other tips and tricks in... read more