I used rice paper and Japanese Sumi ink. This means that you have to paint with committment. The paper soaks up the ink really quickly, so you can't put the brush on the paper and not move it or you'll get a "blob". You have to really decide where to put a line and lay it down without any time to stop and consider it or change your mind.
I did three paintings of Bubba before I had one that I thought was decent.