Besides cheating, probably compliment another guy for a feature that guy A doesn't/will never have. For example: say that you like tall guys when your guy is average or short. Say you like blue eyes when your guy has brown. Compliment muscles when your guy is skinny.
If you're trying to get revenge because he broke up with you or something, let me just iterate the fact that considering your immature response to this scenario, he was clearly in the right by doing so.