basically i set it up as the spnosor is the adveratiser so click on add advratiser and follow the set up for it. then each campaign is one of that sponsors sites. then you go in and put the banners you want for that site... this is basically the database from which you get the ads for the various publishers and zones.
your publishers are your sites or niches or whatever you want to set them up as. within them you have your zones which is specific pages or banner sizes or whatever and they will have specific banners from the adveratisers and campaigns you set up first.
once you have your zones filled with the banners you want to show then you get the invocation code and paste it on the page you want the banners in that zone to show up on.
theres lots more to it than that but thats a starting place at least