In Showderp, we call for a champ. The first person to respond when the previous champ steps down claims the position.
We recommend that champs use a tripcode to prevent confusion.
Showderp viewers will then suggest any six Pokemon: the suggestions can be as vague as "your favorite RU Pokemon", or detailed down to EVs and moves.
Shitmons (such as Heal Pulse-only Slowbro and Black Sludge Shedinja) can be fun for a while, but they will usually serve as only dead weight on a team.
The champ will take the first six Pokemon and mess with the OU tier (sometimes Ubers or even LC) with his or her ragtag band.
After some battles, the champ calls for a new team before battling again, or steps down from the position and call for a new champ.
The cycle of showderping thus continues.

There's a lot of other stuff you can figure out by lurking a bit more.
Have fun, and be most excellent to each other!
These are things. Use them:
pastebin.com/0bYpM0at
memebasemon.com/
Current champ: me