Most of the advice above is great. I would add that I recommend getting a few level 6 accounts and doing 5v5 wars and maxing clan games as much as possible to get your clan level up, just by yourself. Getting to level 5 is pretty easy I did it in several months. At that point you've got decent clan perks and a +1 level bonus that will draw more attention than a level 1 clan. I picked up a few accounts along the way most of which went dormant although one remains active and while he never speaks he fills donations properly and gets his clan games points in.

You're going to want to have a donation account that you can use to fill war needs. To get the +2 bonus at first I used a dormant level 10 clan to donate from my higher account, but then my main's clan dropped from 50 members so I was just able to invite the low level accounts for donations. Was much easier that way.