Aim to be there 30-45 minutes before opening. It takes a decent amount of time to get through security and ticketing. Hogsmeade gets especially crowded 12-5 so avoid then. The Hogshead Inn is a good place for a rest if you catch yourself in a mob in Hogsmeade.
Camp Jurassic is great mid-day bc it can handle crowds and still be fun.
Catch the street shows.
Get the wait time app as it contains maps, showtimes and restaurant info too.