Most of the training, shortlists, tactics can be imported from your own games and transferred over to the online game.
To run a successful clan you got to have a group of guys who all get on, are reiable etc. Do not get too many at first. I would experiment with three or four players to begin with and then add when you know the players are reliable.
Have set times for playing and days where all can play. Most clans usually play twice a week or sometimes three times a week or more.
A set of rules can be drawn to help aid the running of your clan.
I would set up the game on the person with a good, stable internet connection with good upload speed and with a pile of ram. I think macs and PCs can play at the same time.