Water Heater question

We will be taking our first trip (just a weekend for a dog show) this weekend. I remember reading that you can damage the water heater if don't do "something" correctly. I can no longer find the post but it had to do with the water heater being empty..I think. I have a 1996 2518 and you have to go outside to light the pilot. Do I simply turn on the pump and open the hot water valve before lighting the pilot?
Cheri