Controling your ball from the rough so that you can actually hit the green requires a steeper swing, gripping down slightly and a tighter grip so that you can keep the clubface square and a minimum of grass between the clubface and the ball
Keep you putting simple by developing an easy one-two count, take your backswing on the one count and the your through swing on the two count and create a constant pace to your putts
Play the ball back of center, weight forward and pull your left arm in as you swing