To remove glued mirrors from a wall, you first want to ensure you have the proper safety tools and equipment. Glass is extremely fragile, so use goggles and gloves to keep from injury in case it breaks. Lay a drop cloth on the floor as well. Start by covering the mirror in heavy-duty packing tape to reduce its likelihood of shattering. Then, use a shimmy or crowbar to gently pry the mirror off the wall, starting from any gap.