Don't put the barrel directly on a hard surface.
Put your hand, a shirt, jacket... something soft under the barrel.
I've seen that happen more than once. Most recently at a 3 gun match where guys were placing their pistol directly on the shelf inside this shack we were shooting out of.
There was a hunting show on TV where this woman comedian was hog hunting and missed two pigs. They showed footage of her shooting at a target to make sure her scope was in line. In the field she placed the stock directly on a fence post, but when shooting at the target, she had her hand holding the front of the gun and cushioning it from the bench.
Missed in the field and bullseye'd at the bench.
I've also seen folks pull their head up too soon in an attempt to see the results of their shot. Hell, I did that on a gobbler quite a few years back and a doe only a couple years ago.
Stay down on the gun. Open both eyes to see the results, but stay down on the gun as if you are ready to send another shot.
In many 'sports' that is called follow through.
Just to name a few: Archery, Golf, Baseball, Wingshooting with shotguns.
You don't stop the swing as soon as the ball hits the bat, or the club hits the ball.
Same thing with the shotgun. Keep swinging the gun through the bird / clay after you pull the trigger.
A few years ago, I killed a hen turkey while she was walking steadily on a path that I had just ranged a spot at 35 yds.
I floated the pins where I thought they should be for the spot where her wings attached to her body while floating them about 8-10" in front of her, matching her speed.
I remember letting the arrow go and allowing the bow to roll forward no differently than when shooting at a target. The only difference was also allowing my body to continue matching her speed after the release.
I really couldn't believe it when the arrow thumped her. And when I got to her, I found the arrow went in and out where the wings attached to the body.
One in a million shot for me, because we can also talk about the time I missed a deer because I lined up my pins with my dominant eye.
That caused the arrow to hit dirt a foot in front of it...
( I'm left eye dominant and shoot a bow right handed. )