Using a #1 Phillips screwdriver, unscrew then flip open the front half of the case.

Turn the phone on and firmly push it down into the scanner plug.  It is a tight fit by design, and it may help to stand the case upright on a table top.  Push the top of the back shell half over the top of the phone.  When the phone is properly seated, the screen will briefly display "Device Attached."

Reattach top half of clamshell.