Here's some things that worked for me.
Leading up to the meet hit, some singles regularly and practice paused bench esp. holding at start and finish too, but back off as the meet gets closer. A week away, just go through the motions with a decent weight on squats for Monday, Bench for Tues, and just do some cleans wed. then rest up until the meet.
Unless you are right on the bubble of a weight class, don't worry about losing weight for your first meet. Just lift in whatever class you weigh normally. I was at 190 for the 198 class for example, but it really didn't matter. Now, if I was 199 a couple days out, I'd for sure have lost the pound, though.
BtB covered getting the feel of the place and eating and drinking, Ryano covered the opener. I was told specifically to use a weight you flat know you can do. Something like an easy double or triple from your workouts.
You might think you're wasting a lift, but that first squat is overwhelming pressure, so you have to flat out know you will stand up with it. Same with the first bench, as their bench will not be like your bench, so be ready for anything. Deadlift, just go off how you feel because you will be tired mentally and physically from the brief stresses of the day as well as the interminable waiting! Definitely sit a lot! And watch the other groups lifts, they're inspiring.
After the opener, just go from there. Try to hit all three attempts, but if you miss a PR attempt, so be it. Being amped from the crowd will help you though, so don't be shy about giving it a go if you feel good.
Time your warmups at home, see what the minimum you need to be ready. Then add 5 min. Do plenty with very light weights, then 10 min out start ramping it up with singles to about 20-30 lb below your opener. Hopefully, there won't be a lot hammerheads hogging the warmup bars uneccesarily, so get in with a group you fit in with and take turns. If guys are hogging the bars, don't be afraid to butt in and take weights off the bar if you need to. You have to look out for yourself. But, you'll also be surprised at how strong you are on stage with less warmups than normal.
Take, or make a friend there to video your lifts. The people in the audience are very nice and will be happy to video if you ask.
Listen to the judges! They will help you too. Give you advice, etc. Do not be afraid to ask questions of anyone. Everyone there will want to help you. Everybody wants to see you make your lifts.
Read the rule book before! Don't forget socks (like me) or y-fronts or something silly. Check your bag twice. Write your lifts down before hand, saves thinking under pressure as you have to set your next lift right after you lift.
Hard not to feel pressure, but also rememember to enjoy yourself. It was a blast for me.
I am Anton Zdravko Martin!
Best meet lifts: Sq 150 Kg (330 lb), Bench 120 Kg (264), DL 160 (352) @89 Kg (197)
Best gym lifts: Sq 375, Bench 275 (pause), DL 370 @205 or less
Goals beyond my wildest dreams, 600 Kg raw total, 200/160/240
Hack away at anything which isn't essential. Do what you love, and do it often. Fazc.