Like this, kiddo: put your arms out in front of you, bent at the elbows. Now turn them over, palms up. Splayed out flat, fingers relaxed.
There. Perfect. Now I'm going to lay my hands on top of yours. But I'm going to go faster from here on out, fast as I can. You've got to be quick here. Quicker than I can be.
See? It's all about reaction time and who's faster, you know?
There's a catch, though: if I'm faster than you—if I can pull my hands away from yours before you can touch me—it's my turn.
Now you lay your hands on mine.
No cheating; you've got to keep your fingers touching my fingers. Good. Remember to keep your hands flat. Flat and steady and ready.
See? That hurt, right?
(This is a game, a reminder, a lesson: pain in everything I teach you.)