Putting maximum spin on a wedge shot requires the right lie. Specifically, the ball must be sitting up and lying cleanly, with little or no grass behind it. The more of the ball's surface that is exposed to the clubface, the more it will spin. Expect maximum spin when hitting from an uphill lie with the wind blowing against you.
Plant most of your weight on your left (front) leg and lean your upper body slightly toward the target. This will encourage a steep swing, which promotes hitting the ball before the turf. Improve your odds of making a steep swing and precise contact by taking an open stance; this also will prevent excessive lateral movement and restrict backswing length.
During the backswing, keep your weight on your front leg and your upper body leaning toward the target. Restrict body motion as you swing your arms on an upright path. Above all, keep your arms and the club in front of your body rather than letting them swing around to your side or behind you.
CHECK YOUR IMPACT
Freeze and check your impact position in front of a mirror. At impact, the left wrist should be ahead of the ball, the shaft angled toward the target, and the right (back) knee pointing ahead of the ball. The proper wrist and shaft positions ensure that the clubface hits the ball first, then the turf. The right-knee position means the lower body is rotating through the shot.
For maximum backspin, the right (trailing) arm should not rotate over the left (leading) arm through impact. Instead, rotate the entire right side through the shot to promote good acceleration and prevent "scooping" (where the clubhead passes the hands before impact). You want to feel as if you are compressing the ball against the clubface.