To make the polyhedron shown above, I started with a snub cube, then augmented all the triangular faces with prisms. Next, I formed this augmented solid’s convex hull, and, finally, I used the “try to make faces regular” function of the software I use to manipulate polyhedra (Stella 4d, which you can try here). The regular faces are the octagons and the small triangles.
I used the same process to make the polyhedron below, except that I started with the snub dodecahedron.









