In this video there is a clip with John Glover on how-to build a Model A Ford Fender. It doesn’t go through the whole process but you can get a good idea of how someone with a lot of experience looks at and panel and determines what has to done to get the job the simplest and easiest way.

Here is another good example of how to plan for the shaping of a panel. You can see how by using butcher paper and some masking tape he is able to create templates with some shape to it. Doing this gives you a good idea of how much shape needs to be added the panel. Where ever the paper has excess you know that you have to shrink the material in that general area. You might also see that the template needs a few slits in it in order to conform to the surface you want which is any indication where the metal needs to stretch.