That will take a few moments to give you the basics and a lifetime - or longer to master. Here are a few very basic points to start with;
feet in a boxer's stance, not too wide and balanced on both pegs. If shooting a heavy recoiling beast, or a full auto, bend the front knee somewhat. Supporting elbow straight down.
hand under the forearm. You will find out whether to pull back a bit ,or just hold 'er up
trigger elbow straight out, firm but not tight grip with the trigger finger with just the pad controlling the trigger
sights level
take your aim while taking several deep breaths then relax
The sights will wander, so take the slack up on the trigger when the sight picture is right and FREEZE when it goes astray
it will go off when the stars are aligned.
If it takes too long, come down and recuperate, then start the proceedings all over again
It is an art, and very personal, so learn from as many advisors as choose to chime in.