We have taken the following route: established a couple collegiate chapters and as time has passed, we built up our alumnae base -- and also established city-wide chapters. With the alumna involved, we are taking their resources to get incorporated, secure insurance, establish our business structure, etc. Unlike our sisters who are still in school, we are a little more equipped to handle it. From there, you can go on to expanding to other schools. That seems to be the most feasible route in our case.
Keeping alumni involved is the key; it's so tough for students who are on campus to deal with this stuff by themselves.