There's no difference between playing 2 characters and playing dozens of characters. The same steps are taken to set up any configuration. You need a key broadcaster, you need to set up that broadcaster, you need to set up macros for inviting, following, interacting with NPCs and combat.

If you want the quickest setup, then probably ISBoxer. You will also probably want Jamba to deal with turning in quests. There are guides for both in the newbie's threads.