Heck, what can I say? I like it to smell good around here...
Associations with the tarot can lend essential oils a new aspect to their power. Many of the Major Arcana have depictions of flora in the background and while some have no corresponding oils (such as the sunflowers in the Sun) others are quite dramatic (the white rose in Death). Use one or more of the oils drop by drop in a diffuser or mix with water in a spraybottle to spritz the heck out of your room before your readings to promote a little good karma and let those vibes flow~~~~
To learn more on how to use aromatherapy (non-tarot related), please visit AromaWeb and The Guide to Aromatherapy
(the great end all and be all of EOs)
(a no nonsense oil if I ever saw one)