For those of you who are hitting the ball off the toe of the club rather than off the sweet spot, your correction might be something as simple as the distance you stand from the ball. What you might find is that you have really good posture, and you have good extension of your arms at address, but you are standing so far from the ball. Your arms are reaching outside of your shoulders in order to set the club behind the ball. What happens is that when you make your swing your arms will want to come into the ball on your downswing underneath your shoulders, pulling the club back in and catching the ball off the toe of the club. A simple way to fix that problem is to take your normal set up, except start by putting the hosel of the club behind the ball. Then take your normal set up and then pull the club in until the center of the club is behind the center of the ball. This will get your arms underneath your shoulders and allow you to make solid contact rather than hitting the ball off the toe.