Most bottles of essential oils that you purchase online or in stores are 0.5 ounces. I do not know exactly how many drops that is. Remove the stopper from the bottle, and dump the entire contents of the bottle into the mixtures. You will use all of the essential oils. Pour them into a measuring cup, then add an equal amount of neutral carrier oil. For example, if the total amount of all the essential oils is 1/4 cup, then you will add 1/4 cup carrier oil.