Well, plan on a hotel. Better that way. Dinner with the fellas, relaxation....
The most I drive to a local contest is usually an hour before I get a hotel..
Fuel, if going only Saturday and Sunday (not Friday for practice) take however much you would need to fly 8 flights. 6 for the contest, and 1 practice flight each morning.
At a 3 hour drive contest, I usually try to get there the Friday morning to practice.

If you get outta line, try to get back in where no one notices or where it's not scored..
Speed, well, fly where you feel comfortable.

Tips, well, be yourself. Ask everyone at the contest what you should do. They will guide you through...

Bring stuff to drink, and snack on.. Also bring an easy up canopy if you have one..

Good luck!!!!!!!

Chris