Rubbing alcohol on a cotton ball or cloth
Hand sanitizer with alcohol
Dry-erase marker over the Sharpie, then wipe off
Magic eraser with gentle pressure
Baking soda and water paste
White vinegar on a cloth
Acetone or nail polish remover for hard plastic only
Toothpaste with a soft cloth
Wash with warm soapy water after cleaning
Test on a small hidden area first