If your college has wireless access points for the student population, they have no doubt published specific guides on how to use them. There are really too many possibilities to address here. For example, they may have specific software requirements enforced by the Cisco NAC Agent; they may use RSA tokens, or other physical hardware you'll need to obtain.
It could be no more involved than turning on a laptop with wireless connectivity, and pointing to a specific IP (which we wouldn't know) for auto-configuration.