Since the problem does not provide any information to help the process of classification, you should start by identifying one of the three common classes the polyhedron belongs to.
One class of polyhedrons is the class of platonic solids. The polyhedrons that belong to this class need to have all faces the same regular polygon. The following polyhedrons can be considered as platonic solids: tetrahedron (4 triangular faces), cube (6 square faces), octahedron (8 triangular faces), dodecahedron (12 pentagonal faces), icosahedron (20 triangular faces).
Other class of polyhedrons is the class of prisms, regular or irregular.
The third class of polyhedrons is the class of pyramids, regular or irregular, triangular, square or pentagonal, right or oblique.