Before swinging the golf club it is imperative that a golfer put themselves in a well balanced position. The width of the golfers stance and consequently his/her weight distribution is of the utmost importance.
First, make sure your feet are a proper distance apart. Now, what does a "proper distance apart" really mean. Well, TheGolfExpert has a fairly accurate and easy to remember rule of thumb to help you figure it out for you individual swing. Beginning with the shorter clubs (i.e. the wedges) your feet should be just less than or slightly inside 'shoulder width'. The distance between your feet should slowly move further apart as we move upwards up through the clubs and they
gradually get longer. By the time you get to the woods (i.e. the longest clubs in your bag) your feet should be fully outside shoulder width apart (i.e. th insides of your feet, or your arches should be vertically in line with the outside of your shoulders.
As a recap, the two extremes are, slightly inside shoulder width (wedges) to fully outside shoulder width (driver).
Its also important to note that the taller a person is the larger the base required to properly balance. Therefore, the maximum stance width will be wider for a golfer who is 6 feet tall than it would be for a golfer who is 5 feet even though they may have the same shoulder width.