If you can, pull the sub out for starters, plus any loose stuff in the car.
Stay calm and don't worry about anyone else at the track, just focus on learning. Don't worry about messing up, launching poorly, or running slow E/Ts. Just learn. My first time out I made a 17 second pass, it was weak. With no additional mods I ended up dropping that E/T down 2.5 seconds to 14.5. It just takes practice and a few trips to the track.
I would air my tires down to 20-22psi. I don't have any scientific proof that it helped, but it may have helped me pyschologically. Same goes for your fuel level. Obviously fuel adds weight, but unless you've got a FULL tank the differences may be negligible. That being said, my car ran "better" with less than 1/8 tank.
As its been said, avoid the water box. Especially with your front tires, all you'll do is drag water onto the track for your drive wheels to spin on. I used to like to roll past the water box and mash the throttle in wet area around the box. (This was Capitol Raceway, other tracks will probably be better kept.) With the 4.10s the tires would spin enough to throw debris off the tread, but not get all sloppy and useless the way street tires do when you try to "heat them up." I'm talking like 1 second of spin here.
The launch will take time to learn, so try some stuff out and you'll develop a technique.
Again, don't worry about what other people think. You'll only end up being "That Guy" if you do one of two things:
1.)Drag water onto the track with your front tires.
2.)Stage with your rear tires. (Approach the tree slowly, don't roll past the staging beams too quickly
)
Good luck!!