We recommend that you apply your carrier oils before any of the other oils you may be using. Not all carrier oils work well together and you may need to experiment a bit to find out which one works best for your skin. Most experts recommend that you use only one type of oil at a time unless otherwise instructed. If you do need to use more than one then be sure to follow these instructions when applying: (a) Apply the first type of oil (such as tea tree or lavender) at all areas your acne is appearing, then wait for 20 minutes. (b) Wash off the first type of oil with water.