This method of preparation is most often used for roots and barks. You will need to bringing water to a boil, add the appropriate amount of herb, and then bring the preparation to boil and simmer as per the directions until some of the liquid is gone. This preparation will take a few hours. With the Essiac® powder “decoction” you will reduce the liquid from 88 fluid ounces to 72 fluid ounce. Keep in mind that all the glass bottles you use have to be sterilized.