I have a method that works alright for me that you could try. What I do is draw a wing and fuse on Paint. It's an easy program for me not being an experienced drafter. I can generally get the basic shape of my model in there, and I save that. Then I color and draw all I want, and if I don't like it, I just cancel out and load up my "blank" and start over. Save several differnt schemes, and look at each one. I usually start that once I get the model, and while I'm building I'll go back to it. Here's my latest for a Great Planes Ulitimate 40 Biplane. Hours into this, and this also gives you a really good idea as to how much, and basically what colors you need to finish. Kinda helps me buy just what I need.