Have you:

• [x] Modelled experimental objects/part of a possible project in 2D and 3D software

• [x] Shown how you did it with words/images/screenshots

• [x] Included your original design files

• Design files: Right click + Save As

I started an object similar to the polygon using OnShape. It was just my first 3D model. (gif below)

I found this example of polyhedrons that can be a start point here. I chosed this icosidodecahedron, downloaded and printed the file, just to taste the geometry.