The hip turn in a golf swing permits the rest of the body to move. It can be the trigger for part of the swing, and the downfall of a bad swing. Concentrate on getting it right, whilst not thinking about it too much! Golf really is a game of complete opposites and it is easy to understand why there is a lot of confusion in the sport.
The first pointer when talking about the hip turn is that it is just that. It is a small movement of the hips, combined with the legs and upper torso. But, it is not the entire body moving. The aim is that the legs, hips, torso and shoulders rotate to give the swing a wide arc, whilst the head stays perfectly steady. Imagine that your head and feet are clamped whilst the rest of the body turns and you are getting there.
Stage one of the hip turn is the back swing of the stroke. Feel your upper body and arms leading the turn and just let your hips go with the flow. At the top of the back swing, check that the club is pointing where you want the ball to go and then look at how your hips have turned. They should be halfway between the starting point of pointing to the ball and the facing away from the ball. A 45 degree turn, or an eighth of a full body rotation.
If you have rotated more than this the your legs have yielded too much, less than this and you are too stiff and not storing the energy needed to send the ball towards the flag.
Now the fun bit! I pause every so briefly at the top of the back swing. Just long enough for me to think 'hips'. At this point my reaction is to start the hip movement to begin the down swing action. This is a slight left shift of the hips, which drops the shoulders almost vertically, bringing the arms down. There is also a slight movement of the arms to bring your right elbow towards your right hip.
The final part of the hip swing is to open then towards the target slightly. This is the end part of the left shift and will allow the club and arms to pass cleanly in front of the body.
But remember - the head stays still! You are rotating the body, not moving the head.
If you have ever skimmed stones across water then you will know the final hip position feeling from that, even if you don't yet realise that. Pretend to skim a stone and look at where your hips finish off. That is the position you are trying achieve!
To recap, starting square to the ball the hips should turn 45 degrees away from the ball, almost being dragged by the upper half of the body, then start the downswing with a slight left shift of the hips and a turn towards the target, finishing as though you are skimming a stone.
Oh, and did I mention - keep your head still! It is a turn, not moving the whole body!