[header] How to make the arm of death [title] Pour some water or orange juice into a food-grade rubber glove. [step] Leave enough room at the top for tying a knot and for adding gummy worms. [substeps] Since this has the potential to be slightly messy, pour the liquid over a sink to take care of any spills. 
If you're using water, then add some food coloring. Just make sure the hand doesn't get visually lost in the color of the punch--you want to use contrasting colors.