Many golfers try to set up with the weight on the insides of their feet.  This idea is supposed to create stability and keep golfers from swaying while they swing. I was taught this concept as a junior golfer, and I often read this advice in current golf publications.

This idea is flawed, however, because by setting the weight on the insides of the feet, you are changing the natural alignment and function of your legs and hips.  When you move your weight to the inside of your feet, your ankles bow inward as do your knees.  Your pelvis also shifts downward in the front, restricting your hips joints.  These positions keep your body from moving freely and smoothly.

Feet Should Be Flat On The Ground
I teach players that the feet should sit flat on the ground so that your ankles and knees will line up properly over the feet, thus allowing proper rotation.  Sergio Garcia and Annika Sorenstam are great examples of players who set up with the weight flat on their feet.  Both of these players are very consistent ball strikers who hit the ball well more often than not.

If your swing feels tight and restricted, try setting up with your feet flat on the ground.  Don’t pinch your knees inward, but rather let them stay over your feet.  During your swing, allow your ankles to rotate and move freely.  Your swing will feel smoother and fuller and you will strike the ball with ease.