Using a plastic opening tool, carefully pry off the entire SIM/SD card reader component.

Don't worry about ripping the copper foil a little bit, it is easy to put back on.

When reassembling the device, do not attempt to smooth the foil down with your finger. Metal foil can become sharp if folded in a certain way, and you may be cut.

The battery may be removed without removing the SIM/SD card reader. Simply peel back the copper foil from the opposite end of the device, stopping just before you reach the SIM/SD card reader.