Just like playing with a laser pointer with my kitten. Move that little red dot over there, she follows it. Move it over there, she stalks it and then when she thinks she got it cornered, she jumps on it. Move it up the wall, she jumps up hoping to grab it. And then I make circles around her, and she spins like top. Quite funny and fun to watch! And it never occurs to the kitten that it's just a red dot that can't be touched, cornered or captured. But as a rule, never, never point your laser beam at the eyes.