Make sure essential oils are stored in a cool, dry place. Never store in a plastic container. Most essential oils can last from 1 to 3 years. The exception is ANY citrus oil. Citrus oils last from 6 months to 1 or 1 years.
Essential oils can last for several years, but the freshness tends to fade.
When you buy an oil, write the date on the vial. Use ONLY essential oils. If you re opting for a just a soak, you can simply add about 5 to 10 drops into the warm to hot running water. There are various types of diffusers which you can use in your home, office or even your car. Some are electric, while others require candles.