Tear a piece of wax paper off of the roll and place over the ball. Twist the end and set aside.
Tear off two feet of foil and wrap into a tube. Cover the tube with wax paper so that the stiffener doesn't stick to it. These will be the arms (you can add more foil to make the arms longer).
Twist the ends of the arms so they don't come unraveled. Bend in the middle and stick into the coffee container. Shape so the arms don't come out and they stay straight.
Place the head on top of the container with the twisted portion down inside.
Cut three lengths of cheesecloth (about 18", or to cover your mold) using the scissors. Before cutting, check to make sure the pieces will be long enough to cover the mold.
Place in a bowl and squeeze fabric stiffener on top to cover. Coat the cheesecloth thoroughly with stiffener. You want enough to get it pretty wet without making it "stiffener soup."
Pick out one piece of cloth at a time and squeeze out excess stiffener. Drape over the top of the mold. You'll see that the ends curl naturally quite nicely. It's pretty lightweight so your mold should hold it easily.
Repeat with the second and third pieces of cheesecloth, arranging them slightly differently as you place to cover areas that you didn't get before. Let dry overnight.
Remove the mold from the bottom of the ghost. You can help assist with the process using a hair dryer if needed. Make sure all parts are completely dry before displaying.
Paint with glow in the dark paint and add eyes and a mouth if desired!