Unfortunately I wouldn't count on a May 1 guarantee.
Newly admitted students, congratulations!
Let me give a bit of advice/info about the next steps, in case you haven't gotten it yet. This is all info you'll get eventually (much is in the packet, or will be covered during APS).
Apply for university housing as soon as possible, if you're at all interested. It's nonbinding, and the sooner you apply the more likely it is that you'll get a unit that you want.
If you haven't, apply for a GS scholarship. It's free money!
You'll have to come to campus for an Academic Planning Session (APS), which they'll start offering in May and continue through Orientation Week. They'll detail how you register for classes, you can take a campus tour, meet current students, and get all sorts of important details. Once you pick an APS you should schedule an appointment with your adviser soon after (you can do the next day) to actually register for classes. You should also schedule a meeting with the financial aid department.
During the APS they'll ask you to develop 3 schedules for the fall. You can get a jump on this by poking around the GS Bulletin (Courses | General Studies
), the Directory of Classes (CU Directory of Classes
), and culpa.info. If you're going full time you'll be taking university writing, so try to find 3 classes you want to take your first semester. You can take most 1000-3000 level classes.