It looks pretty easy in the movies. But in order to properly aim, shoot and place the slug where you are aiming, there is a little more to it than Hollywood makes it out to be. Many factors are applied when taking aim with a pistol. You must consider variables such as wind, if your target is moving or still and other factors which may be involved in every shot.
Listed here are some very basic steps that can help you become a better shot with your pistol. But the very best way to develop handgun profenciency is practice, practice and more practice.

SOME BASIC STEPS:
Read the instruction manual for your gun before using it for the first time, or if you haven't used it in a while. There are some very important tips provided by the maker of the handgun that will aid you in becoming familiar with your gun.

Wear the proper safety gear to protect your ears and eyes.

This is a must. Many people who have been shooting for many years will tell you that ear protection is somethiing they wished they had practiced many years ago. Earmuffs or earplugs will protect against the report of the weapon that will send your ears ringing - even with a handgun as small as a .22 caliber. Safety goggles protect the eyes from flying shells, hot gasses and lead particles as they're ejected from the weapon. Again, even the smallest caliber handgun emits a certain amount of discharge that could get into the eyes. Protect them because they are the only two you have.
Lift the pistol, making sure the barrel is pointed downrange and the downrange area is perfectly safe. Be sure to keep your finger outside the trigger guard. Hold the handgun pointing upward. Never point in a target direction unless you are completely sure of you target. Notice we have not mentioned loading the weapon at this point. This is for a reason. That will come next and only then.
Insert the magazine for a semi-automatic or rounds for a revolver. If the pistol is a semi-automatic, load the chamber by pulling back the slide and releasing it. This will chamber the round. Keep in mind you are pointing the weapon downrange at all times.

Grip the weapon very firmly-- making sure your finger is outside the trigger guard at all times. Wrap your non-dominant hand around the left side of the frame (if you are right handed, the oppisite way if you're a lefty) aligning your two thumbs to point toward downrange. The goal is to have a very firm grip with no air spaces between your hands and the grip. Make sure your thumb clears the slide or hammer. If not, you might lose it! There is nothing more painful or humiliating than having the skin of you thumb pulled back by the slide of a handgun.

Stand in the proper firing stance. Your feet should be shoulder-width apart, with the foot that is opposite your dominant hand in front. Blade your body and stand with a slight lean forward. Not too much. You should be balanced. Not over balanced. The elbow of your dominant hand should be almost completely straight. Stand as if you are ready but not overly stiff - as you may be there a little where.

Align the front sight with the rear sight. Unless you are already experienced, it is best to aim by viewing only with your dominant eye. Close your other eye. Now make sure of the following:
a) The front sight is aligned in the notch of the rear sight so that the top of the front sight is level or just a little lower than the top of the rear sight.
b) Make sure that the gap between the sides of the front sight and the left and right sides of the rear sight notch are equal. When all set, maintain your focus on the front sight and bring your weapon to bear on the target. You should see the sharply focused front sight touching the bottom of the blurry, unfocused bullseye. This is when you have proper aim.

When you have achieved proper aim, gradually squeeze (not pull) the trigger with a constant pressure. If you jerk or "pull" the trigger, your aim can be thrown off. Once you begin pulling the trigger, keep pulling it at a constant rate until you are startled when it goes off. It is best to time firing with your breathing. Take a breath, exhale half of breath, then fire a round.
Fire numerous rounds making sure to retake aim, because recoil will throw off your alignment. Do not rush it. Make sure to aim each time going through the same motions each time.

When you have either emptied the pistol or you are through shooting unload your weapon and double check to make sure it is unloaded. Open the action of the pistol and properly store it safely out of the reach of small hands.
Remember that safety is the number one concern. You can have a very good time shooting your handgun - make sure it's a safe one.
Billy Willis
http://www.lonestarholsters.com