It's also fun to roll up a piece of tape and stick it to their fur. My cat loves to play that game. He has to figure out where it is, then he throws it back at me to do it again. 😃
Have you noticed that their nerves go all goofy and their skin starts twitching when you put it on the area just above their tail (where it meets the spine)...and there's a specific location they can't reach. So they go in circles or jump back trying to get at it? That's when my cat spits it back in my face and we both start laughing.