My warm up is similar to Rodger's lots of stretching and getting warm but just enough with the weights to get me prepped for my first attempt.
Bench warm up would go something like below
135x5
185x4
235x2
285x1
325x1
attempts would be something like 365, 390, 405
deadlifts I warm up very little for as you are already warm from your first two lifts and being in a crowded room half the day.
my deadlift warm up is something like below
225x3
315x1
405x1
My first deadlift attempt I generaly treat like my final warm up and would be about 495, then 530-535, last 575 or so.
Don't be afraid to use Wendler's recommendations for your first meet attempts which are 85% of your target max for 1st, 92.5% for 2nd, 100% for final.
Flights are generally 10 to 12 lifters so approximately 10 to 15 minutes between attempts.
Yes to food and lots of it for me. I generally bring 3 peanut butter and jelly sandwiches. A full bag of trail or chex mix, almonds, apples. Most importantly make sure you have plenty to drink. I bring a 24 pack of water plus gatorade and a few cokes for caffeine.
Plenty of food and staying hydrated to keep the energy levels up for me. I try to conserve my energy between lifts sometimes even taking a short nap between lifts if there are lots of flights but you aren't likely to be able to pull that off in your first couple of meets.