The most popular grip is resting your left index finger on top of your right fingers. Do not interlock your fingers.
It is ok if your club pulls out of your fingers a little when you rehinge it, as it potentially creates more speed.
Don't focus too much on exactly when your wrists hinge. Let the momentum of the club do it for you.
This is a great drill to feel the momentum of the club and where it is in relation to the ball.