I haven't tried the system myself yet, though I too am very interested in doing so. From what is in the 2.5 book, it seems like the biggest things that will be needed to get one off the ground is a map with the appropriate supply points and a set of objectives for each player in the campaign. The rule book describes these as being secret and known only to the player they are given to, which means that you might almost need a "campaign master" who runs the whole show and may or may not actually play in the campaign.
This will require a little imagination, as Spartan never got to release a full set of documents for a campaign using this system for us to model our own efforts off of!