Coin flipping: best done in groups, as a competition. Try to control the outcome of a coin flip, flipped from a reasonable (not too far, not too close)

distance from a level surface. After a period of practice, set up a competition sequence of 10 coin flips, where you compete on who gets closest to 100% (or 0%) heads. To win, you should try to make the initial conditions of your coin flips as consistent as possible. Notice and control height and distance to the surface, as well as where on your hand you place the coin, how it is oriented, and how hard you flip it with your thumb. In your preparatory training, see what makes for the best consistency: a soft or a hard surface; hard or limp slipping; etc.