Diving Division 1 college walk on?

I am a diver and I am interested in being a walk on this fall.... how do I go about this? I am already accepted and enrolled at the school I want to attend for the fall, but I just don't know how the process works. Do I email the coach and ask him if I can be a part of the team? What do I do? I'm not looking for a scholarship of any kind, just a spot on the team so I can participate in the sport I love. If anyone has been a walk on before or knows what I should do please help me out!