Hi Bril,
The width of your stance will vary depending on the club you are using and the shot you are hitting. For example, your stance for a driver will be wider than with your wedge. Also your stance may be slightly wider for a large-hard 7 iron than your normal-stock 7 iron shot. This will be further explained in Chapter 4.
Don’t get caught up in exact placements of your feet, there is no set width to go by for each golf club or shot. Allow yourself to step into a shot and have a sense that you feel athletic and balanced for the shot at hand. Play around with it a bit when you are on the range. Try exaggerating the width in your stance to feel how wide is too wide, then begin moving your feet toward each other to have a sense of what is too narrow. After discovering what is too wide and what is too narrow, find a place in between that feels strong and athletic that will allow you to move spontaneously throughout your swing. You might find that a comfortable width of stance to settle on for a stock 7-iron might be just slightly wider than shoulder width apart.