I don't skate, its my daughter, but the competitions are great and well done for even getting on the ice never mind entering competition.
As for what to expect, you need a nice outfit,you need to be there 30-45 mins before your competition starts, you will get a warm up on ice before your group start, then you skate your best and will be marked by the judges, if they have a photographer a nice pose is needed for that.
Music has to be given in at the desk but thats your coaches job I think, all you need to do is remember what you are doing, warm up stretches etc off ice before hand too.
The day before, there should be a patch session for you to go on and get used to the different ice and a draw for skate order is generally done the night before, sometimes earlier.