Here is the fist pencil sketch I did (about 6"x6").
Once the first sketch was approved I blew it up and re-drew this one at the actual print size.
This is the final color vector art. I started this process off by creating black vector line art of my tight pencil art then making an overall shading halftone (ended up dark blue/green) and finally filling in all of the spot colors and creating the separations.