Cart before the horse, friend 10-Ring.
The elements of shooting ANY firearm--not just a shoulder arm or a handgun--are the same. And, the objective is the same--to hit the target as close to the point of aim as possible.
Here, then are the elements that make a good shot:
Sight picture--your sights placed so that the object to be hit is in the same relation each time. Some use a 6 o'clock hold (target on top of the front sight), some use a center hold (target cut in half by the front sight). Whatever it is, it should be the same each time.
Sight alignment--front sight post level and centered in the rear sight.
Trigger control--steady pressure to the rear until the gun fires.
The challenge is to do all three--AT THE SAME TIME--without disturbing your sights.
That's really all there is to it.
And, your best place to start is from the prone position, with a .22 rifle. Why a .22? You can shoot more without damaging your budget.
Use all of the things you know about shooting a handgun. Transfer that to rifle shooting. Of course, there are a few important additions:
1. Breath control--even more important than handgun shooting.
2. Stock weld--the placement of the cheek upon the stock of the rifle to bring your eyes in alignment with the sights.
3. Eye relief--having your eye in the same position every time.
4. Stock pressure--pulling the rifle back tightly into the pocket of your shoulder, each and every time.
Concentrate on the basics first. Get yourself a good .22 semiauto, and go out to a 50 yard range. Set up a target that allows you to see the sights in good relief. Now, using the same sight picture each time, fire off five-round groups.
Your objective at 50 yards is to achieve a shot group that can be covered with a nickel, with the irons. After you do that, move the target to 75 yards. When you are getting nice tight groups to point of aim, then transition to the big rifle.
Good luck, and good shooting! Remember to shoot that big rifle slow, let it cool at least 1 minute between shots, and 5 minutes between groups. This will preserve your barrel and leade.
If you want some break in tips, let me know.