Aromatherapy uses a lot of different types of essential oils and one popular type is infused oils. This is an age old technique of getting the essential oils out of the plant and involves soaking the herb in oil for an extended period using gentle heat - typically the sun. Over time the essential oils leak out of the plant and become infused in the base oil.
These oils are great for creams and lotions and they can also be mixed with essential oils for aromatherapy. The great thing about infused oils is they are already diluted so if you want to use them topically, you can with no ill effects.
Infused oils are great for aromatherapy because they are less expensive than some of the essential oils that are extracted using more costly methods. They smell great and can be used for massage or even as healing ointments for skin irritations.
The best part about them is you can make them yourself! All you need is a glass jar that has a tight fitting lid. Get some of your favorite dried herb or herbs as well as some of your favorite cold pressed carrier oil. You might be tempted to use fresh herbs, but the moisture in them can encourage mold to develop so your better off using the dried versions. Combine the herb and carrier oil into the container and cover it. Then just put it in a sunny window for at least 24 hours.
Once the herb has steeped in the oil long enough, you need to filter it with cheesecloth or a fine mesh strainer to get rid of all specs of the plant. Be sure you do this diligently since any particles of plant may cause your oil to spoil.