Step 1: Cut the top off
Use the rotary tool to cut off the top of the switch box, except for a strip along the open face, so you can attach the electrical socket to the box.

Step 2: Assemble the compartment
Screw the electrical socket to the open face of the switch box. Then, screw the faceplate to the socket.

Step 3: Position and trace box
Pick a position for your compartment where an electrical outlet wouldn’t seem out of place.

Step 4: Avoid the studs
Run a stud finder over the section of wall where you want to put your box. If it detects a stud, pick another spot four or five inches to the right or left. When you’re sure the new spot is stud-free, trace the back of the switch box on the wall with the pencil.

Step 5: Cut drywall
Use the rotary tool to cut out the pencil outline. Then, place the item to be hidden in the box and push it into the hole until the back of the faceplate rests snugly against the wall. To retrieve the item, simply pull the faceplate away from the wall, and remove the box from the hole.

Step 6: Clean up and hide stuff
Clean up the drywall dust and dispose of any evidence that might give away the real function of this innocent-looking electrical outlet.