The grip is our only connection to the club, yet it is so often overlooked.
A good grip allows you to hinge the club correctly into a square position at the top of the backswing, and then deliver the clubface consistently without any need for manipulation.
Often the right hand causes the issues, all too often creeping underneath the club so the grip is sitting in the palm rather than the fingers. This leads to tension in the grip and restricts the release of the clubhead through impact.
To improve your right hand position (or your left hand for a left-handed player), take a ball and hold it against the club in the same way shown here. From here, make a few practice swings and feel how the club hinges into the square position.