Rub graphite from a pencil along both sides of the zipper teeth
Apply a small amount of soap, wax, or lip balm to the teeth
Gently work the zipper up and down to spread the lubricant
Remove any fabric caught in the zipper with tweezers
Clean dirt or debris from the teeth with a soft brush
Straighten bent zipper teeth with pliers if needed
Check for damage to the slider and replace it if worn out
Avoid forcing the zipper to prevent further damage