Vote for your best and least favorite episodes. It goes something like this:
Best: SpongeBob's House Party
Worst: Whale of a Birthday/Karate Island
Just make sure you list the entire episode! Check TV.com's SpongeBob episode guide for all of the episodes. Once an episode gets one vote off, their out! However, voting for it as the best episode gives it one point, which if voted off, it loses that point, but it's still on! Also, you can't make the same vote more than once!
(look above at example)