It's important to shoot accurately, but it's also important to take care of your body while you shoot otherwise your shooting will suffer. What I mean is that as your day progresses you get hungry or have to go to the bathroom, for example... So if you neglect your body you suddenly realize that you are starving and think about when you can eat instead of that 3/8" killzone in the wind at 16 yards that needs your full attention.
I make sure to keep a water or two and some snacks in my bucket seat. The water I might not even touch if the day is cooler, but once it gets hot I need to make sure that I don't get dehydrated. And I may eat before the match at 6:30, but not be done with the match until 1. For many this is your regular times, but for me I tend to eat at 6:30 and then have an early lunch at 10:30 or 11, so by 1pm I am not a pleasant person to be around if I haven't eaten since breakfast. So I make sure that I carry some snacks to tide me over for a later lunch on those days that I shoot. I might even have a bit larger breakfast than usual so it lasts me longer. Consider more proteins in your breakfast that will take longer for your body to burn.
And the bathroom can throw a wrench into the works. As you sit there taking a shot you suddenly realize that you've been holding it in for 3 lanes already. I'm pretty sure that tenses your whole body up...not good.
The point of all this is to pay attention to what is going on around you but to also pay attention to what is going on within you.