Important: Make sure to switch off
HTC Desire 650 dual sim before removing the card.
Make sure your phone is off. Open the back cover from the groove at the bottom.
Slide the nano SIM card and micro SIM card out from its slot.
To replace the back cover, first align it onto the top part of the phone. Then align the edges and press down on the back cover from top to bottom along the edges until the cover clicks into place.