Fading or drawing the ball, can be made very complicated, or quite simple. The easy way involves the right thumb (left thumb for left-handed golfers).
To fade, take your grip with your thumb resting against the hand. That is, eliminate the gap between the two. This stiffens your wrists which causes you to be late squaring the clubface at impact.
Ben Hogan described his grip in his book, Five Lessons, as having the thumb and hand pressed tightly against each other. This is a fade move, and as we know Hogan did everything he could to avoid hooking the ball.
I would not recommend tight pressure. The different location of the thumb will be enough.
To draw, do the opposite. Widen the gap between the thumb and the hand. This loosens the wrists, squaring the clubface early.
This is not to wrap the thumb around the handle, but just to move it a bit farther away from the hand than usual.
Of course, you will have to adjust your aim appropriately.
This trick is courtesy of Vivien Saunders in her book, Advanced Golf, a book you really should own and study.