When you want to use cannabis oil, you should first heat it. You can do this by placing the bottle in a warm water bath. Furthermore, you should heat it until the oil is warm. You should never heat the oil until it is boiling. If you do, then the oil will not be as effective. After that, you should place it in a syringe and use it to place the oil under your tongue. Always follow the instructions on the label when you want to use the oil.