Remove the metal handle from the suction cup. It's easier and safer to grip the suction cup's base instead of the metal handle.

Be very careful when opening the iPhone so that the cables under the display are not severed.

There is a rubber gasket between the silver front bezel and black display assembly. A bit of force is required in this step to separate the iPhone's display assembly. It may help to rock the suction cup back and forth to remove the display assembly.

Use a small suction cup near the Home button to gently pull up the bottom portion of the iPhone's display assembly.

If the display assembly is too damaged to allow the suction cup to adhere, tape with a strong adhesive such as duct tape or packing tape may be used.