Application - Damage to zipper teeth or zipper tape can cause the slider to come off one or both sides of the zipper. Use the damaged area to retrack the slider back onto the zipper tape when doing a temporary fix.
Skill - Remove the teeth at the damaged area and lightly singe the tape if it has frayed. This will leave an open area where the slider can be maneuvered back on to the zipper tape.
Patagonia Repair Tech Tip: Maneuver the slider as if parallel parking a car. Start at an angle, back it onto the zipper tape, and then straighten out.