I suggest getting a bottle with a squirt valve at the top the ones I seen used most is a soaked out Joy or Palmolive dishsoap bottle. Then just squirt the water directly into the dogs mouth and they will drink it. To get them started squirt some around the mouth and they will lick it off believe a few times of that and they will open their mouth and let you give them a drink.
Make sure the water has no soap taste to it after you soak it out. You will most likely have to change water several times to get it to taste good.