Take a ball and throw it overhand. That action is the same action your trail arm does in a golf swing. It is a universal action in sports. Whether you are throwing a ball or shooting a basketball, the wrist and hand react the same. Throw sidearm then underhanded. You start to feel how your hand and arm work on different planes. Put that same action into your golf swing. When you throw a ball, there is no tension in your shoulder socket. That should be the same in a golf swing.
Practice working on swinging the club with the lead arm. This drill helps you keep your shoulders level, not slide your body, stop the up and down motion in your wrists, and get your hips out of the way as you pivot through the ball.
Practice working on swinging the club with the trail arm. This drill helps you keep your shoulders level, not slide your body, stop the up and down motion in your wrists, and get your hips out of the way as you pivot through the ball.