A diffuser is the most effective way to unleash the best essential oils into the air, but if you don't have one (they run from $25 to $200), you can drip oil into a bowl of steaming hot water. In either case, use one or two drops of one oil at a time. Stand a few feet away and take 10 deep breaths, then breathe normally. If you stick within the safe time limit and open a window when you're done, you can practice aromatherapy every day.

https://www.youtube.com/watch?v=6mPOl3Oh6Fk