As student of shooting, I have always sought to understand things at a fundamental level. For me, shooting is a journey. Here is a description of where I am along the path.
Be aware. See first. Think fast and then act without hesitation.
There are only two essential things you must do to hit a target.
1. You must align the barrel with the target.
2. You must pull the trigger without disturbing that alignment.
All else – stance, grip, sight picture and all the fundamentals – is helpful, but not essential.
The amount of time and effort you must put into barrel alignment and trigger pull depends on the distance to and size of the target. Speed is achieved by spending only the time necessary to make the hit and no more.
Inside ten yards, you can shoot both eyes open and be very sloppy with the trigger because the target subtends so much angle. At contact distances, you don’t need to use the sights at all.
Beyond 10 yards, sight alignment and smooth trigger pull become more important. Past 50 yards, you can still hit, but your sight alignment and trigger must be very clean.
Can you think of any sport where the players close one eye? You need binocular vision for depth perception and peripheral vision. It does help precision shooting to close one eye and it may even be essential to hit a particular target. Don’t spend any more time than is necessary closing one eye or looking at the sights. See what you need to see. Search for it and focus on it.
Your eyes can only focus at a single distance at any given time. For full situational awareness, you should be constantly transitioning near and far. When you need a precise shot, you must focus on the sights, but in follow through, you must fight to shift to a more distant point. You must scan not only right and left but near and far.
When not shooting, keep your gun down so it doesn’t block your field of view nor cover anything you are not willing to destroy.
See what you need to see. Get the sight picture you must have for the accuracy that the situation requires.
Provide the trigger pull needed to attain the required accuracy. Follow through, assess the target, repeat as necessary.
Follow the target to the ground.
Check your buddy, check your gun, reload, stage your magazines.
Look for the next threat.
These ideas are simple, but shooting is not instinctive and it is not easy.