It's red! No, it's blue! Or is it green now? It's hard to plan moves when you're dealing with a piece that can be any color of the rainbow!
Other than that, though, it's just like a regular piece. You can make matches with Chameleon Pieces just like you do with regular pieces: if it's an Apple, match it with Red Apples; if it's a Pear, match it with Green Pears. It's as simple as that!