I do very, very, very simple, skimpy doodles, nothing too committed. Because people tend to fall in love if they like it - if you color it in and they like it, then they want exactly those colors, even if they were just indications. You really have to do it as simple as possible so they can concentrate on the idea and composition. And then all of the energy goes into making the final piece. And the final piece can be anything - it can be a drawing, a painting, a collage - and usually, it's obvious what that should be. Usually, the idea dictates what medium you use.