Always ALWAYS open with a weight thats lighter then the one you know you can nail. IE if you max out bench at 250 then do something like 185, just so your on the board. Then split the difference on your next attempt and go all out on your last. This way any curves that are thrown in can be felt out throught the three attempts.

Kind of slack on the hydration until you weigh in, most times there are an hour to a few hours inbetween weigh in and lifting time. So basically nill the water weight down (if its a problem) until weigh in then hydrate heavily. If weight isnt a problem then make sure your VERY well hydrated from up to 2 days in advance.

Eat a big meal of carbs right before you lift (again if weight isnt an issue). Its fuel man, and you'll be glad you have it.

Sleep VERY well, get atleast 10 hours for up to 2 days in advance.

*Between now and the meet (this weekend?), the only thing you should be doing is resting.
*If you need to make weight, try not to dehydrate too much and make sure to take in plenty of liquids after the weigh-in (early weigh-ins are the best if you have them!)
*Pay attention at the rules meeting prior to the competition - sometimes you can get an idea of what kind of pause they'll be looking for
*Wait for the commands "Press!" and "Rack!". Unless you time them perfectly, you'll probably get redlighted - if you pause too long, you might miss the weight. Watching the judges give commands to others before you might make it easier for you to "anticipate" the calls.
*It's nice to have your own hand-off person if you can - someone you're used to training with.
*Don't change your diet much the day before or of the meet - the last thing you want is an upset stomach on comp day because you made changes!

Oh, and don't get baby powder on your hands before you head out for deadlifts!

*be sure to time it right in getting your equipment on before your place in a flight, and have someone help you
*don't warm up too soon or too late before your first attempt. You want to be warmed up but not fatigued for your first attempt.
*eat little bits of food continually throughout the day, but nothing that you aren't used to eating