Identify the zipper type and the damaged area
Remove any loose thread or fabric caught in the zipper
Slide the zipper slider off the teeth if needed
Align both sides of the zipper tape evenly
Reinsert the zipper teeth into the slider from the bottom
Pull the slider upward slowly to test engagement
Use pliers to gently crimp the slider if it is too loose
Replace the slider if it will not hold the teeth together
Reattach the zipper stop at the bottom if it was removed
Sew the zipper tape back into place if it came detached from the garment
Test the zipper several times to confirm it works smoothly