Simple advice is often best: follow through!
I like to dig deep into the science of your golf swing using my Trackman radar as well as the apps on my iPad, but many lessons I give are boiled down to the simplest of terms and a general message. This week I had a spell of Members who hit the ball much better, very quickly by simply showing them how to follow through to completion and that was all that was needed. The reason the follow through is such an important aspect of your swing is that it completes your body rotation, but also keeps the club accelerating through impact, which is vital for optimum distance.
In the picture above from over 100 years ago, there is no guessing the direction which the ball was hit.