Put on the black pants, white shirt, and vest. Tuck the shirt and vest into the pants.
Tie the ascot or tie around your neck and tuck it into the vest.
Put on the black jacket and shoes.
Wrap the cape around your shoulders and neck.
Take a plain white plastic mask with a rubber band around the back, like this one.
Carefully remove one end of the rubber band from the left side of the mask.
Cut the mask from left to right across the forehead to the bridge of the nose, around to the underside of the nose. Continue down to the mouth, around it, and to the chin.
Reattach the rubber band to the top of the mask with a stapler. You may need to use trial and error to make sure the mask will stay on your head.
Place mask on your head.
Paint your face on the right side to look like the deformed phantom. Only do it where the half mask will cover, so that the deformed face remains hidden until it is removed to shock everyone. Use white for your face and black around your eyes and on your lips.
Pull on the gloves.
Put on the fedora hat.