Patchouli essential oil is made from a plant, originally from India, where it is known as puchaput. It was popularized in Europe during the 1800s and again rose to infamy in the Unites States during the 1960's when "flower children" and "hippies" wore the scent religiously. It has a strong aroma and gets even stronger in scent over time. So if you are interested in utilizing patchouli for its aromatherapy properties (which are many--anti-depressant, antiviral, digestive, diuretic, as well as fungicidal--to name a few), then applying the full-strength oil, in small doses, might be recommended. For all other applications of the oil, you should dilute it.
Choose an organic carrier oil. Jojoba oil has the greatest trans-dermal properties of all the carrier oils, which means that the benefits reported to be present with any essential oil, when added to the carrier, will find the greatest absorption rate into your skin.
Mix 25 drops of the patchouli oil with 2 oz. of jojoba oil. This is a great massage blend; a subtle aromatherapy treatment that can be applied to your pulse points directly on the skin--under your neck glands and inside wrists. The aroma can also be dispersed into the atmosphere of your home through an air diffuser.
Put eight drops of patchouli essential oil in one tub of bathwater as another way to enjoy a softer application of this oil. This makes for a safe, pleasant and therapeutic soak.