I am trying to create an effect where i have a subject drawing a picture on a white piece of paper and as he draws it, it appears on the white tee shirt that is laying next to him on the table. I don't even know where to begin
Motion track the tip of the pen/pencil. Create a path from that. Apply that path to the brush effect.
Though without knowing a little more about the details its really hard to say as off the top of my head I could think of a few other ways that may work better, or may not work depending upon the shot composition, shot length, picture complexity, etc.