Usually, I create my herbal oils using the folk method. Simply explained, I fill a mason jar with the dried herbs of my choice, fill the jar to the top with my carrier oil of choice, seal the jar tight, and allow it to macerate for at least 3 weeks(shaking the jar daily and insuring that all the herbs are submerged). However, there are certain instances when I do not have the luxury of time to wait for the oils to be ready so I take a short cut by using my crock pot.
To make an herbal oil in your crock pot, you will need 1 oz of dried herbs for every 8oz of carrier oil. I advise against using powdered herbs, as they absorb the oil like a sponge and also clog the strainer when you are ready to strain the oil. Place the herbs and carrier oil in your crock pot and heat on the lowest setting for about 5 hours. I stir the herbs every so often with a wooden spoon. When done, strain out the herbs with a fine kitchen strainer(I usually use fine cheesecloth), pressing out the oil with the back of a spoon. If any herb particles come through the strainer, re-strain the oil through a coffee filter. Stored in a cool place, herb oil will keep several months.
I prefer the traditional method of creating herb infused oils, but this method is perfect when you need to have some herbal oil sooner rather than later:-)