All you need is:
White muslin cloths
Disposable plastic cups
String
Nail
Scissors
Sharpie pen in black (or paint or googly eyes)
1) Cut a tiny hole in the middle of the muslin cloth with scissors
2) Very carefully use the nail to pierce a hole in the middle of the cup base
4) Turn the cup upside-down and place the muslin cloth over, joining up the two holes
5) Feed string through the two holes, and create a knot in the inside of the cup
6) Using a Sharpie, draw on a ghost face
7) Hang as a ceiling decoration using the excess string
Easy!