Good advice above.
Years ago, a friend had a boss whose string hand shook so bad behind a little bush (Arizona small, Charlie Brown Xmas tree size) as a buck came in that he, the boss, couldn't make it happen. Guy did rodeo, like bucking horses and stuff, so no stranger to adrenaline. Tough man.
My system is this: when a buck comes in, I look at my string hand. Calms me.
In other words, I have a calming sequence, like we all have a shot sequence.
I
Around now, my practice is often a stumper-judo and my binos. I look for deer, does, and get kinda close (150, 60 or so yds), stumping a bit as I stalk into the hidden places from their eyes... Just watching, learning the body again. Not being able to arrow does in AZ means we get to be close to a lot of does. Doe is a dog sized animal here, often. In a way, no big deal.
And a buck is just a deer like a doe, but with silliness coming out its head. A meat tube, with antlers. This calms me too, even though I know there is more to it.
Never look at antlers, yes, have had a bow hand shake and squeak the leather on a handle and alert the buck.
My two cents...