Swimmer Tips?

Today is our first league meet of the season for my schools swim team.
I kind of volunteered for the 500 Freestyle, which I've never done. I think I'll win against at least on of the other swimmers that volunteered, but I don't know about the opposing team's swimmers.

My Events:
200 Medley Relay ((Back or Fly))
500 Freestyle
200 Freestyle Relay
100 Backstroke

I can only guess my relays. Individual events are for sure.

Any tips on the 500? How to find a steady pace? When to start building for a strong finish? Breathing? Anything? Hahah

Thank you in advance.