Immediately afterwards, turn around while still holding Square, and press Down on the D-pad to switch to the item used. Face forward, and use the Dragon Head Stone again while holding Square.
Equip the Dragon Head Stone with the soul or item you wish to duplicate directly after it. Then, unequip your head slot item, and equip either the Grass Crest Shield or Cloranthy Ring. Go to a bonfire, and interact with it so there are no enemies around you. Their health and attack values are raised nearly twice as much from the first playthrough. The enemies will also be more difficult during the second playthrough. However, you do not keep unique items like keys or Embers. Select New Game + mode to begin a second playthrough with all previously obtained weapons, armor, and souls. Successfully complete the game, and save when prompted to unlock New Game + mode.