The usual methods of application are in baths, in massage or, to diffuse it in the air.

Essential oils are very potent and must be used carefully. Some should not be used during pregnancy, some may irritate the skin, some should not be used by persons with high blood pressure or any medical condition and some should never be used at all.

With the exception of lavender oil and tea tree oil, essential oils must ALWAYS be diluted before use. Dilute 1 drop to at most 3 drops of essential oil in 1 teaspoon of Carrier Oil before using it.

Here are some uses for essential oils

Baths

In general, you can use many essential oils in baths. To use, fill your bathtub with warm water. Dilute 4 drops of essential oil in 1 tablespoon of cold pressed vegetable oil like Soya oil, almond oil or grapeseed oil and add it to your bath water.

Massage

You can use the non-irritating essential oils in massage. Make a massage oil by mixing 2 drops of essential oil in 1 teaspoon of cold pressed vegetable oil. Mix well. Use as a massage oil on your body. Note: The first time you use a particular essential oil, do an allergy test with 1 drop of the oil mixture first on your elbow wait 24 hours for any averse reaction. If you are not allergic to it, then try massaging it all over yourself. Better still. Get your partner to give you a nice relaxing massage.

Diffuse in the air

If you have a essential oil burner, then use it.
Otherwise, you could put a few drops of the oil in some dried wooden shavings, in some pot pourri or any porous material to scent the room.
Another way is to put a few drops of the oil on an empty bag of a vacuum cleaner and vacuum the room. The air expelled from the vacuum cleaner will diffuse the oil in the room.