Create Fellowship: http://brainking.com/en/Fellowships - there should be a link I think at the bottom of the page to create a new fellowship.

Restriction: none really. If you plan to have "adult" type language, it is recommended you put that warning in the description so those who are offended by it will know not to join.

Tip: Fellowship name should be some-what unique - not the same exactly as a game, discussion board, or other fellowship. So for example if you have a backgammon fellowship, don't just call it "backgammon" - but something a little unique - for example "backgammon fellowship"

Other then that, jump in and start to play. Feel free to ask questions here - plenty of people who will be happy to help!