Warning: do not attempt these exercises while operating heavy machinery, or in a crowded elevator. Or really, just don't do it at all.
1. Tapping the forehead with your eyes closed: Learn the basic moves
2. Tapping with your non-dominant hand: Master the subtlety of it all
3. Tapping in rhythm: Tap your way to the beat
4. Tapping with a pair of chopsticks: It's like playing the piano, but without the skill