Once you have loaded up to the top of your backswing, you should feel that you were in a coil and powerful position ready to start your downswing. Starting your downswing with the hips is an essential part of generating a powerful and accurate golf swing and a great way to improve your ball striking.
The hips should initially move laterally towards the target before they start to unwind in a rotational or spinning action. This should encourage a good weight transfer from the rear foot to the front foot and then a nice powerful uncoiling action to deliver the golf club at speed and on the right path.
If the hips only rotate, the body weight may remain too far behind the ball resulting in fat and pulled golf shots. Conversely, if your hips purely slide and don't rotate at all, a golfer may cause too many pushed golf shots and may feel unbalanced and lacking in power.
To practice the correct motion, setup face into a mirror and watch how your hips move during the start of the downswing phase. A little bump left towards the target and then a big belt buckle rotation through to the target. This should give you the correct feeling of shifting and clearing your left side.
This will result in more accurate and powerful golf shots.