The ball must be played as it lies, except as otherwise provided in the Rules.
(Ball at rest moved – see Rule 18)
13-2. Improving Lie, Area of Intended Stance or Swing, or Line of Play
A player must not improve or allow to be improved:
the position or lie of his ball,
the area of his intended stance or swing,
his line of play or a reasonable extension of that line beyond the hole, or
the area in which he is to drop or place a ball,
by any of the following actions:
pressing a club on the ground,
moving, bending or breaking anything growing or fixed (including immovable obstructions and objects defining out of bounds),
creating or eliminating irregularities of surface,
removing or pressing down sand, loose soil, replaced divots or other cut turf placed in position, or
removing dew, frost or water.
However, the player incurs no penalty if the action occurs:
in grounding the club lightly when addressing the ball,
in fairly taking his stance,
in making a stroke or the backward movement of his club for a stroke and the stroke is made,
in creating or eliminating irregularities of surface within the teeing ground or in removing dew, frost or water from the teeing ground, or
on the putting green in removing sand and loose soil or in repairing damage (Rule 16-1).
Exception: Ball in hazard – see Rule 13-4.
13-3. Building Stance
A player is entitled to place his feet firmly in taking his stance, but he must not build a stance.