Apply a suction cup to the back of the phone, as close as possible to the center of the bottom edge.

If the back cover is cracked, the suction handle may not stick. Try lifting it with strong tape, or superglue the suction handle in place and allow it to cure so you can proceed.

Pull on the suction cup to create a gap between the rear glass and the frame.

Insert the tip of an opening pick into the gap and slide it to the bottom left corner.

Leave the opening pick in its place to prevent the adhesive from resealing.