Take some crackers with you, the moon is made of cheese you know. Drop your drawers, that would be the ultimate butt moon.
Freeze to death. Get bombarded with solar radiation.
Practice the high jump, long jump, and pole vault.
You know - it's cold outside and there's no kind of atmosphere.
learning to do handstands, headstands, walk on your hands, invent a ballet about being on the moon, invent moon puns, watch all episodes of button moon, manufacture cheese from moondust, watch that wallace and gromit where they take a trip to the moon
play munchkin :)
Get the moon rover car and jump things
Bounce and collect rocks. You could also plant artificial flowers to trip out the next visitors.