Today's golf coaching encompasses many different theories, philosophies, and models. The bottom line to all of the types of instruction you receive is being able to feel the difference between how you currently perform your swing and how you want to perform your swing.
One tool to help your swing
Many people practice with, and many coaches rely on, swing aids. A valuable asset in your improvement process, swing aids should provide your body with the feelings necessary to eliminate a swing flaw and result in an improved swing. There is a plethora of swing aids on the market, and they are not all created equal. You first have to determine what part of your swing you are trying to improve, because not all swing aids will help you with every part of your swing.
You and your coach can determine the right one for you
It should be easy to use, easy to understand how to use, and not require you to place your body in a contortion to use it. It should be easy to store and fit in your bag. A very important test that most golfers do not think about, along with some coaches, is whether the swing aid provides immediate kinesthetic feedback. In other words, the aid should tell you through an immediate feeling, whether you are performing a swing correction properly.
Swing aids can be pricey. If you cannot afford a swing aid, chances are you can engineer a very workable alternative with things lying around your house. In choosing an instructor, look for an instructor who will invest time, money, and professional reasoning in the use of swing aids.
Can you feel the difference?
The bottom line is you should use swing aids that help you "feel" differences between what you are taught to achieve and how you are currently swinging the golf club. The easy way for you to remember whether a swing aid is good for you is to keep in mind that a swing aid does not have to look sporty or cost a lot. It just has to provide you with a difference in feeling to be effective.