According to Frank Costanza, the Festivus celebration includes three major components:Link (thanks, Andria!)
The Festivus Pole
The tradition begins with a bare aluminum pole, which Frank praises for its "very high strength-to-weight ratio." During Festivus, an unadorned aluminum pole is displayed, apparently in opposition to the commercialization of highly decorated Christmas trees, and because the holiday's creator, Frank Costanza, "find[s] tinsel distracting." Local customs vary and you may be able to decorate your pole with non-threatening plain decorations, or ordinary green garland.
The Airing of Grievances
At the Festivus dinner, each participant tells friends and family all of the instances where they disappointed him or her that year.
The Feats of Strength
The head of the family tests his or her strength against one participant of the head's choosing. Festivus is not considered over until the head of the family has been pinned to the ground. A participant is allowed to decline to attempt to pin the head of the family only if they have something better to do instead.