During the base to final leg of the circle to land approach, the pilot overshot the centerline of the runway. On short final and at a low altitude, the pilot still had not attained alignment with the centerline of the runway. The pilot made a left turn, and then a right turn, attempting to align the airplane with the runway. During the right turn, he dragged the right wing on the snow-covered ground, damaging the outboard leading-edge slat.