It's a sticker, throw it away...
But, if it was signed by God or something, you'll have to get it off with the adhesive still attached. Kinda depends upon the makeup of the sticker, but try taping over it with masking tape to keep from stretching it. Then, get it really hot with a heat gun and try to slowly peel it off. Good luck, but it would be much more fun finding newer and cooler stickers.