The key with hardpan lies is to clean out all the loose debris around the ball and then set up to make a more vertical swing so that you hit the ball cleanly and minimize the effect of the hard ground
Sam Snead thought that the absence of tention and target awareness where critical in the swing so keep your eyes on the target and club suspended in the air
Practice putting with your wedge forces you to hit the blade of the wedge directly on the equator of the ball, which is exactly where you want to hit the ball with your putter too