I have a Glacier Bay medicine cabinet model 122-757. The instructions show the hinge stretched out on the door to mate up with the cabinet. I cannot get the hinge to work to configure it the way the instructions show. Is there some trick to this? I do not want to force anything. The instructions do not mention anything about loosening any screws to make the hinge operate.

Try without the instructions.

Those are European hinges which remain hidden, mounted on the back side of the mirrored door. Glacier Bay framed mirror medicine cabinet 122757 | eBay Open the hinges and try to first mount the hinge to the door.