It's easy, just like the 'write a story about the person above you' game...You basicly make up a 'situation' that the person above you gets in...then post a 'result' or 'finisher' to say what happens afterwards. Lol.
EXAMPLE.
Situation- (name here) thought mocking Superman over him wearing his underwear on the outside was a great joke.
Result- (name here) is clobbered by superman.
EASY HUH!? Well, I can't make a post since noone is above me, so...go on.