In terms of a stress relief device, the use of essential oils can shift our mood with just such power and certainty, when we understand how to tap into it. The scent of lavender is one of the most calming and balancing of all the oils, and for that reason, you see it (or smell it) in many products for inducing relaxation and sleep -- like bath oils, bath salts, pillows, etc. The important thing when using essential oils is that they must be purely derived and of high quality -- meaning, the distilling process and the original herbs or flower source must be pure.
There are a variety of ways to use essential oils and I highly recommend trying them out. You can diffuse the scent into the room, create a "blend" using the essential oil and a carrier oil, such as jojoba or sweet almond oil, or you can put a drop on a cotton ball or handkerchief -- they can also be used in massage. If you are interested in learning more about essential oils, I recommend the website www.oilladyaromatherapy.com, since its owners represent a wealth of experience and integrity with teaching about and using this precious gift of nature.
I found aromatherapy to be a wonderful addition to my repertoire of caregiver tools -- for my own care and for my mother -- I had a custom blended oil created for her, which I used regularly. She found it very comforting and even the process of putting the oil on her skin was soothing and nurturing-- to us both! This is a transformative and very effective therapy for dealing with Alzheimer's and other forms of dementia, or for cancer patients and their caregivers, for children with autism, and many, many other uses. And, of course, for self care for the caregiver! Check my resource page for further information, links, and books about the subject.