First you turn off the water valve leading into the toilet tank. Second, you leave a massive dump in the toilet and go away. The third step involves another person, hopefully the host of the party or some squeemish bimbo, discovering the cornsnake you just left. This person usually freaks when it becomes apparent that it is not simply going to be flushed away. (No water...you drained it in step 2 and it didn't refill)
There is usually 10-15 minutes of disgust and panic while someone figures out to turn the water back on and send the offensive offering to king-coiler heaven.
"The host of the party was a real prissy I'm better-than-you-type, so I decided to dry bog the hallway toilet to liven things up a little."