A bit too late for Christmas, but for future reference - it rather depends on the purpose of the Spritzer. Skin care? A linen spray? a general room spray?
The problem with an EO spritzer is the that essential oil will NOT dissolve in water. What you will need is to first dissolve the essential oil in a solublizer...either VERY high proof vodka, Everclear, or Perfumer's alcohol if you have access to it, or a substance called Polysorbate 20.
Mix the essential oil into twice as much of your chosen solublizer, then add distilled water.
Now...the amount of oil will depend on the proposed use:
For 4 ounces of distilled water use:
8 to 10 drops for the face
30 to 50 drops for an all over body spritzer
80 to 100 drops for a room spray/air freshener
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