Peel off as much residue as possible with your fingers or a plastic scraper
Rub the area with a cloth dampened with warm soapy water
Apply a small amount of rubbing alcohol to a cloth and wipe the residue
Use white vinegar on a cloth to loosen the sticky residue
Apply a little cooking oil or baby oil, let it sit briefly, then wipe clean
Use baking soda mixed with a little oil or water to gently scrub the area
Try a commercial adhesive remover that is safe for plastic
Wash the plastic with soap and water after removing the residue
Dry the plastic completely with a clean cloth