The black stickers between the 4 foam pieces are there to protect the unit's warranty. If you try to send the device back to Sony after poking through said stickers, they will not accept it as the device has been tampered with.

Poke through said stickers and unscrew the 2 10mm Philips J1 screws beneath those.

Insert the blue plastic tool into the corner of the bottom faceplate and slide along the edge.

It will be a bit difficult as there is adhesive holding the faceplate to the unit, but with it bit of playing it should come off with ease.