Use an oily lubricant, such as petroleum jelly or furniture polish, as suggested by the Antique Restorers website.. Apply a moderately thick layer to the water mark, and leave it on the area overnight or for a minimum of 8 hours.
Rub the water mark with a soft, clean cloth or an old cotton T-shirt. Use a circular motion and continuously rub the area until the water mark is gone.
Remove all the remaining lubricant with another soft cloth.
Dampen a soft, cleaning cloth or old cotton T-shirt with some mineral spirits, as suggested by Reader's Digest. You can get this at discount or furniture stores.
Rub the white ring or water mark with the rag, using a circular motion. This will remove the wax without damaging the finish.
Rub some furniture wax into the area if it looks dull after removing the water mark. This will restore the shine.