We play it generally the same as the other mentioned on this site. Rather than use a cup with water we use a full beer with its cap upside down on the top of the bottle. Object is to knock it off of the bottle with another cap. Usually five hits to a beer. Three in a row results in chugging of the rest of the beer. Rebounds are good, meaning if it bounces back you get another shot. If you knock the cap off yourself, you drink. That's it . Enjoy.