The lead hand on the grip needs to be what I call “built up on top” of the handle with two knuckles showing and in the fingers while the face is square. This gives you leverage to “Chop” the club and have control of the face. The trail hand needs to cover the lead hand thumb within the lifeline. I call it a hot dog in a bun. Overall the grip is the lifeline to the club and will work with the timing of the swing for the club face to be consistently “square” at impact. It is one of the most important fundamentals of a great player.