This helped me out tremendously when I was competing.
Make a checklist at home so you know what to bring. Knives, tongs, forks, paper towels, cleanser, dish soap, gloves, etc...etc... You'll be surprised at just how much stuff you need. Don't forget the small stuff. This is what will break you more than anything else.
Bring a small dry erase board and an old school dial kitchen timer. Pace out the distance from your booth to the turn-in table so you know how long it takes you to get there and back. Write this on the white board. You'll be surprised at how long it takes. If you have a partner or a dedicated runner it will help, but a lot of 1st timers show up and it's just them doing everything so you need to take this into account.
Write the turn-in times on the board for each category, then set timer for 10 minutes before 1st turn in. Now you know how long you have to make 1st turn-in and what meat you're supposed to be doing. Be as early as possible as per the rules from the cooks meeting because you will need all the time you can get to make the next turn-in. You will be surprised how fast time flies. It should only take you 3-5 minutes tops to set up your turn-in box but if something goes wrong, you have a few extra minutes to reset your sauce or get new slices or fix whatever happened. Because SOMETHING ALWAYS HAPPENS!!!. Get your turn-in boxes garnished and ready before you need them and have them in the cooler to keep it fresh so you can just pull and use them without futzing with'em.
The big reason for the white board is to remember the order of meats.
It's a double blind judging, and usually the person at the turn-in table will examine the meats in the box, but sometimes with a lot of entries, they're just taking them in and the first time the box is opened is when the table captain presents the box for appearance to the judges. I can't tell you how many times, the box was opened and the wrong meat was inside. Judging for X and got Y. Oooops. DQ'd.
The white board just helps to keep things straight and when you get back, reset timer for how much time is left, less 10 minutes.
Once you get into a rhythm, you should be fine.
Bring a notebook. Write down when you put the meat on, what the temp of the smoker was, and anytime you opened the smoker for any reason like to mop or spritz. The reason is that you will be surprised at how often you actually do this. It's a nervous thing almost every first time competitor does. They're worried about what's happening, what the temp is, etc... and they open the cooker way too much to "check" and everytime you do, you loose heat. So now extra time is needed to get back up to temp. Write down temps of the meat at various times. eg: the 6 hour mark, 9 hour mark, etc. When the meat stalled and hit the plateau. What temp this occurred at. How long it sat there before moving again and how long it took to get to full temp. What meats were added at what time while others were still cooking and what those temps were.
All this information will be invaluable for your next contest to help you get your times down better and better so you know if your cooker is cooking fast or slow and how long it takes to make adjustments to get them done in time.
For big cuts, even if they're done a few hours early, they'll hold temp. for chicken and ribs, these cool off too darn quick and if they're done early and you try an hold them, they can get over cooked really fast and the meat ends up falling off the bone and won't hold together.
So in conclusion and sorry for the long winded response, take notes, take notes, take notes. but have fun too. Just remember, you spent a couple of hundred dollars to enter, another couple of hundred on meat and how many hundreds on all the materials. Take this seriously and you could win back some of that investment and maybe even a few grand or more.