what we found worked the best. get aluminum foil, local rewards store card, hair dryer, magic eraser, and goo-gone! lay a piece of the foil over the decal, heat with hair dryer on high and work the decal up with the store rewards card. keep repeating until the decals come off and the glue residue is left. i found using goo-gone and a magic eraser removed the glue residue. then clean the shower like normal. 