Power off your iPhone
Work in a clean, well-lit area
Use a hair dryer on low heat for 10 to 20 seconds if the protector is adhesive
Gently lift one edge with a plastic card or fingernail
Slowly peel the protector off at a low angle
Apply a little more heat if it resists
Avoid using metal tools
Clean any leftover adhesive with a microfiber cloth and a small amount of isopropyl alcohol
Check the camera lens for residue or dust before turning the phone back on