Local Service Sorority--Need Help!

[Artoo]

Hi everyone,
I'm interested in starting a local service-oriented sorority here at Oregon State University. I'm just in the beginning stages because right now I am just a non-degree seeking student (I'm applying for full-time admission for this fall).
Does anyone know if I can start the process right now, or do I need to wait until the fall? Is it up to the college that a non-degree seeking student can start up an organization? My guess is probably, but any input would be much appreciated.
Also, how many fellow students should I have on my side to do this? I'm new here and don't know a soul!