Cerunnir has started a clan called xCF. You may want to join it and practice with them for a while to get a feel for it.
The reason I'm not in a clan is because, in my experience, when you play with your clan buddies chances are that most people will not want to play against you. And, if you play against another clan you had all better be good, because most likely that other clan (aka: 5 buddies who are all communicating and coordinating 100,000x better than any pub team) is going to beat the ever-loving fuck out of you.