Golf can be an amazingly relaxing sport where the player can enjoy beautifully manicured courses, pristine lakes and wondrous tees along the fairways. Of course, golf can be a royal pain, as the average player never notices those wonders of nature, instead spending his time sending errant shots into lakes, topping golf balls that barely go 50 yards and wanting to wrap his club around the nearest tree. All of these problems stem from one thing--a bad golf swing.
The most common (and hated) mistake is the shank, which causes the ball to go flying off in the wrong direction. It is caused by the golfer's swing coming down on a bad trajectory and hitting the ball with the hosel, which is where the shaft meets the clubhead. To correct this, focus on keeping the clubhead straight on the downswing. If that does not work, try over correcting the swing by focusing on the "toe" of the clubhead. That should bring the swing in line.
Speeding up a swing is a major problem. A player feels she needs to add power so she tries to swing faster, but that is a mistake because it really causes a host of swing problems. To correct it, work on the tempo of the shot. A simple trick is to get a metronome (the little clock that piano players use to keep time) and use it when practicing. Mimic the movement of the gadget's pendulum to time the swing.
Moving the Head
A common problem that few golfers realize they have is moving the head early. They take their eyes off the ball and look to see where the shot is going. This breaks up the flow of the shot. Golfing great Jack Nicklaus use to have his coach hold his head in place by latching onto his famed blond hair. If Nicklaus moved his head, he would lose a clump of hair. While somewhat extreme, focus on never moving your head during a shot.
A Stance Befitting a Linebacker
A golfer is supposed to stand with his legs at shoulder-width apart, but apparently many golfers think they are the size of a pro football player, because they spread their legs out so far. This takes power away from the shot. Focus on keeping the legs at a proper distance, and power and accuracy will improve.