Wash the area with soap and water
Warm the sticker with a hair dryer or heat gun on low
Lift an edge with a plastic card or plastic scraper
Peel the sticker off slowly
Reheat stubborn sections as needed
Remove leftover adhesive with adhesive remover, rubbing alcohol, or citrus cleaner
Wipe the area clean with a microfiber cloth
Wash the spot again with soap and water
Dry the surface completely
Apply car wax if needed to restore shine