When you understand how the body is designed to move, proper shoulder rotation becomes easy. This is why and how we hinge the wrist.
There is a way your chest, hips and hands move and a way they do not move. Here is a drill that will help you strengthen your feel for impact.
Proper arm rotation maximizes momentum into the ball, while maintaining path. Here is the first step towards getting your arms to rotate properly.
Each one of these skill pathways is a concept. When you learn each segment of arm rotation, adding a club to the sequence is not difficult.