Starting along the edge opposite of the hinge, insert a plastic opening tool between the screen and the backing to begin separating the small clips holding the backing on.

Work along the edge and then up the sides, separating the clips with the plastic opening tool.

There is adhesive underneath the slot for the SD card so you will need to slowly apply some force to break the adhesive.

As the back is separated from the device, be careful to not lose the power button. It may come loose and fall out.