First start by peeling off the outer rubbery covering on the bottom of the device.
CAUTION: This part is very fragile, so it is recommended that a blow dryer is used on the covering to heat it up. Simply blow dry the covering while slowly peeling it away, and the covering will not tear.
The inner metal casing is latched inside the outer white plastic shell, so insert a pry tool underneath the metal casing and pry it apart from the shell.