Sprays are best used for its energetic impact. Add 10-15 drops of essential oil per ounce of alcohol. This is very similar to making a liniment. Alcohol should be used rather than water. Alcohol has a cleansing effect just by itself and seems to more evenly disperse the oil. Sprays are a great place to use the oils that are caustic or sensitizing since you are not spraying directly on the skin.
Spray is one of the many methods of using essential oils.