Ideally it serves one. Add the alcoholic contents first, a shot of each and then top it up with coke, but make sure that the amount of coke goes just over the amount of alcoholic drinks already in the glass, ideally 4 parts alcohol and 5 parts coke. It does sound a bit of a mess of drinks, but when put together right it's surprisingly good, the southern comfort makes it mellow, the schnapps and rum give it a sweet taste and the vodka gives it a bit of a kick. Give it a go!