The back swing needs to have certain components present such as a full shoulder turn to help generate power. But the back swing is only there to set up the through swing which is much more important as it involves actually striking the ball.
 
Assuming the back swing has been completed successfully, here is a step by step guide as to how players can swing through the ball to a full finish position.
 
1. The first thing to move during the down swing should be the hips. The right hip should begin to rotate around to the target. This movement sets the whole down swing into motion.
2. As the hips begin to turn through the ball, the hands and arms should drop down from the top of the back swing. The feeling should be that they are falling to earth, or that you are pulling a rope downward. This movement will help the club swing through on an inside to square swing path.
3. As the hips continue to turn, the body follows with weight shifting laterally on to the right leg. This will help players strike down and through the ball with iron shots and generate power with the driver.
4. Coming into impact, the angle built up during the back swing with the arms and club begins to degrease. This unhinging or ‘un-cocking’ of the wrists deliver power into the shot.
5. At impact, the hips should be continuing to rotate adding power.
6. As the club swings through the ball (hopefully with a square club face to the target line), the arms extend and point the shaft straight down towards the target. This extension adds power and accuracy.
7. As the club lifts upwards the body follows, continuing to turn until the hips, belt buckle and chest all face the target.
8. If the hips have turned successfully and the weight transferred correctly, you will be able to finish the swing with most of the body weight over the front foot and balanced up on the left toe.
9. The club should have released fully and have come to rest across the shoulders.
 
Within this sequence there is room for manoeuvrability and differences in technique. A quick look at the swings of great players will show this. Phil Mickleson, for example, has a vastly different swing than Tiger Woods, but both are exceptional players.

However, using these guidelines, left handed golfers will stand a better chance of hitting more successful shots using a more consistent technique.