I'd start by laying all of the tools out on the floor/bench and
arranging them in the same way you envision them sitting in the
cabinet. Then you can move, shift and re-arrange until you figure out
shelf / drawer sizes, shapes and how you want the tools grouped. If
you want cutouts for your tools to fit in, you could even try getting
some stryofoam and cutting it. That should give you a template for
making the real thing.