The practice starts at 8:30 A.M. but I'd get there an hour or two before the gates open an hour before the practice starts. The first 100 people gets an arm band for autographs just ask them at the gate if you are interested in autographs after practice and they will tell you where to go. Once you are inside the gates there are games and stuff for your daughter to do but bring something for her to do as you are waiting to get in the line is long. They sell Soda and Water inside but if you place the water deep enough in your backpack and cover it up really well they won't see it. If your music device is small just stuff it in your pocket and there should not be any problems.
Cameras I see all the time.