There are several common methods for constructing 3D polygon meshes, including box modeling, extrusion modeling, and primitive modeling. Box modeling uses subdivision and extrusion tools to split faces and edges or extrude existing faces. Extrusion modeling creates a 2D shape profile and extrudes it into 3D to follow an object's shape. Primitive modeling connects basic 3D shapes like cubes, pyramids, cylinders and spheres. Other specialized modeling techniques include sketch-based modeling for low-detail forms and 3D scanning of real-world objects.