Peel up one corner with your fingernail or a plastic card
Pull the sticker off slowly at a low angle
Warm it with a hair dryer for 20 to 30 seconds if it resists
Use a little rubbing alcohol, vinegar, or soapy water on the residue
Let the liquid sit for a minute
Gently rub the residue with a cloth or sponge
Use a plastic scraper for stubborn spots
Wash the area with soap and water afterward
Test any liquid on a small hidden area first