Follow these steps:
Go to the Fanpop Main Page or to one of the Club's Tabs that can be found on the Fanpop main page (Animations, Movies, Television, Books, etc) and you will see a large green button to your right that says "Create a New Club". Press that button and fill out the information. Then your club will be active.
Tips:
1. Make sure your club is not a duplicate.
2. Upload content even when you have no Fans. They will come, make sure they have some stuff when they do come!
3. Be a good owner and don't abandon your club. Stick with your club and participate.
Here is a guide to Making a Fanpop Club that I may or may not have written:
link :)
I really may have written it!