1. Take a break in the middle of the day
This isn't a fun suggestion like the others but it's an important one. So many meltdowns and short tempers can be resolved by going back to the hotel and napping or heading to the pool. Not staying in a hotel? There are little places in each of the parks to sit down away from the crowds and the noise to recuperate. If you have children who normally take a nap, take that nap. You'll be thanking yourself later.