The pull hook starts left of target and then curves further left.

It is usually the result of a strong grip and the ball too far forward in the stance which opens the shoulders.

This encourages an 'out-to-in' swing path and a closed clubface at impact.

Weaken your grip to a more neutral position (turn hands to the left).

Check your aim and alignment, pick your target and place a club along the line of your feet, place another club parallel to this one and position the ball in the middle of your stance.

Check your aim is where you want the ball to go! The ball being further back in your stance will delay the clubface closing through impact.