In my multi-media piece, A Basic Golf Swing, I talked about assuming a grip that is based on the way your arms are built. Taking your grip that way, and not in a generic manner like you see in books, contributes greatly to keeping the clubface square throughout the swing.

This is something I figured out by studying functional anatomy, but later I did find references to this advice in three golf instruction books I have, none of which you may never have heard of.

Here are the ways that each one describes what to do.

The whole purpose of the grip is to position your hands upon the club in such a way that they will return to their original natural position at contact. Throughout any swing, no matter how you grip the club, the hands tend to return to their normal position at the hit. Normal position of the hands is how they fall naturally when you stand up straight and let your arms dangle to the sides of your body.
Mickey Wright, Play Golf the Wright Way.

Your hands should be placed on the club the way they hang naturally at your side. Try this out for yourself. Bend slightly from your hips and let your arms hang in front of you. Note where the back of your left hand and the palm of your right hand face in relation to an imaginary target. That’s the natural position in which your arms and hands hang. They are going to want to return there at the bottom of your swing, just when you are striking the ball. So if you make any radical departure* from that position when you put your hands on the club, you’re asking for trouble.
Al Geiberger, Tempo.
* Better: “…make any departure…”

The trick is to find out at what angle your left hand is in while it is relaxed, for this is the angle your hand should be in as it holds the club. Leaving the left hand where it is as it hangs down, place a golf club in your left hand. As long as you do no conscious turning of the left hand* as you hold the club handle, you have the correct hold with your left hand. The same applies to the right hand— there should not be any turning*.
Phil Galvano, Secrets of the Perfect Golf Swing.
* Better: “…turning of the left forearm…” and “…not be any turning of the forearm.”

Do this. It will change everything for the better.

One more note. The first two excerpts say your hands and arms return to their normal position at the hit. They return much earlier than that, literally moments after you take the club away.