A normal student ticket gets you down there.  At some point during the season they require you to be an O Zone member to sit in the O Zone.  That just means you need the current O Zone t-shirt on.  They have been lenient early in the season in the past, but I think they will be stricter with the crowds we will see this year.

They have signup booths at the games or you can go to the Marketing Department in the Convocation Center during business hours.