Several entrepreneurs and companies that advocate the skill of dice throwing (notice I didn't say influencing or control... just "throwing") manufacture and sell "practice rigs."
A typical rig mimics the far wall of a craps table, with a flat surface that has a felt base, and "alligator" walls. You place this on a table to simulate the back of a craps table and standing a prescribed distance you are supposed to be able to train yourself for throwing dice for when you are in a casino doing it "for real."
I never understood why you should invest in one of these practice rigs? I think you can accomplish the same thing using aluminum foil spread out on a bed or on a table. Here's why:
A practice rig is supposed to allow you to throw the dice in a measured way so that they bounce and hit the back wall in a controlled manner -- meaning -- they don't fly all over the place.
Well, in reality, your practice rig can never duplicate the surface or bounce on any craps table in any casino. In fact, no two craps tables can have the same bounce.
So that brings us to the second purpose of a practice rig which is providing a surface for the dice to hit so that they bounce or roll straight ahead. Well, you don't need a pricey practice rig for this -- all you need is a sheet of aluminum foil.
If you lay the aluminum foil on a bed or table the foil will show how the dice "hit" with the impressions that the dice make on the foil. What you want to see are impressions from the flat edge of the dice hitting the foil and not the impressions of the corners or the "points" of the dice.
If your dice hit on the corners or points there is no way to influence which way they will bounce or roll.