How to line up your iron sights on a handgun.

Your front and rear iron sight should be lined up so the three posts have equal height across the top, forming a straight line. As the sight posts align you want equal light on both sides of the front side. You place the front sight over the target so that it cuts the target in half. You want the top half of the target above the sight and the bottom half of the target below the sight so you can no longer see it. In a marksmanship situation, you want to put all your focus on the front sight. In a defensive shooting situation, you want a flash sight picture such that your front site is on the chest of the target.