(Optional) Shorten the zipper. Coats that go past the waist often don ... 6. Remove any stray threads from the placket. If you don’t have a placket under the zipper, you can skip this step.

Keep adding coats until the teeth are substantial ... If there's something caught in the zipper, like a loose thread, you may need to remove it with a pair of tweezers first before you try opening ...