Do you really think I'm going to tell you which clan is the best, and why? Let's go step by step.
If you ask around, every clan will say, "Yes, WE ARE THE BEST..." and after this they will add things like "but we need more oportunities", "we are too young to go to the lans", "our conections are too bad", "we don't have a home page", "what's an OSP ?" o_O If you say any of these things, then you have nothing of what a good clan needs!
First of all, decide which game you want to play with your friends. Later you'll discover you can have different squads which play different games. You might also discover that making a clan with your neighbours is not good at all. So let's say you chose Quake 3 TDM. Good, the first step is done.
Secondly, now that you are a Quake 3 team, you should find at least 5 members, and all of you have the game at home. All of your members should have a good conection, and learn "The secrets of Quake" (Such as timing quad and other things..Maybe I should write a column about them too!). Once you consider you're a real team, you should find a member with some webmaster abilities, because the clan's website will speak for you!
The third step is to make clear who will lead the clan.
You need someone with motivation, organization, and the ability to boost morale when needed. It's also a good thing to train: every day, or twice a week if you're too busy. Join a league or a ladder (and please, dont fail any of the dates, or you'll have a default, and that's what you call being a newbie.)
With time you'll be able to assimilate more members, and finally can add some staff members, being the "right hands" of the leaders. That group will be the support of the clan, but if they start to be inactive and stop editing the website, etc ... the clan will go down !
But don't take my word for it, just an example! ask some of the best clans around like SK (recently ec4 winners) and cK (last KIT winners).
