To burn oil, add water to the top of the oil burner, and then add several drops of oil to the water. Light the candle underneath to heat the oil, which releases the fragrance into the room.
The water should take up two-thirds to three-fourths of the top of the burner. Water helps dilute the oil, as pure oil creates too strong a smell and can be irritating to sinuses. Add a bit more oil for a stronger smell and a bit less for a more subtle scent. A drop or so should suffice to increase or decrease the strength of the fragrance.