Insert the plastic opening tool into the crevice between the camera and the battery of the phone. Using a gentle prying motion, lift the end of the battery and remove.
After removal, recycle the defective battery appropriately.
Insert an opening tool in the bottom crack between the front and back plates and use a gentle upward pull to separate the back case from the front case.
Side buttons/controls may fall from their place in between the back and front casings.