I commence to take the club back with the left wrist principally, and well round the right leg.
The moment the club-head leaves the ball, the left knee commences its bending movement.
This bend of the left knee should be gradual and even, and should not be completed till the club has reached the top of the swing (it is a great mistake to suddenly bend the left knee at the beginning of the stroke, as this creates a jerk and spoils the even rhythm of the swing).
During this time the wrists continue working together in taking the club to the top of the swing, when they should both have turned underneath the shaft.
This turn does not come naturally, but I think it will do so if the wrists are allowed to describe a true arc.
I am convinced that this turn of the wrists is the keystone of the structure on which the whole fabric of true swing is built
Downward Swing
The wrists start bringing the club down; care should be taken not to allow the arms to go away from the body, otherwise the arc described in the upward swing will not be repeated.
The club is brought down predominantly by the left wrist, the right doing very little until the hands are opposite the right leg, when it begins to assert itself, bringing the full face of the club to the ball.
This action of the right hand combines to accelerate the speed at which the club-head meets the ball.
Assuming that the club-head is traveling at its highest speed at the moment of contact, and the right knee working properly, the follow through is the natural result.
The right knee starts to bend towards the ball at the moment of impact, and the weight is thrown on to the left leg, which has gradually resumed its original position.