We can unfold a 3D polyhedron by cutting along its edges and laying its connected faces on the 2D plane. When faces do not overlap, the result is called a net. Similarly, a 4D polytope can be unfolded into 3D space by cutting along its ridges. Beautifully, all unfoldings of the 4-cube, 4-simplex, and 4-orthoplex are nets. Each ridge unfolding corresponds to a spanning tree on the dual 1-skeleton, which is the graph shown below. Source code available here.

Click on the blue nodes of the graph below to unfold the polytope. Your current node is highlighted in orange. Nodes that cannot be reached from your current node are drawn in black. Once drawn, edges cannot be removed except by pressing the "reset" button. Click here to watch a one-minute tutorial video.