Cardboard Surfboard

Hey guys, so I have been looking into some new material. Cardboard. I am thinking of making a 5' 6"×23"×3" similar. Basically a mini simmons. I am using the website sheldrake. They have the material list and the dxf files, but they don't have very many instructions. So hers my thinking. I am probably going to hand cut and then sand down any bumps. I have been watching some videos but they aren't very good. I was wondering if anyone has done this, and if so, maybe shoot me some tips.