Castor oil has been used for centuries as a home remedy to treat a variety of medical conditions, according to "Foundations of Nursing." Castor oil is used to treat mild acne because it simultaneously moisturizes skin, triggering the body to produce less acne-causing sebum, and reduces inflammation associated with acne, according to "Cosmetic Dermatology: Principles and Practice." Consult a dermatologist if you have not achieved your desired results within six weeks of treating your acne with castor oil.
Cleanse your skin gently with a facial cleanser. According to "Braun-Falco's Dermatology," it is best to splash the face with warm water to dilate pores prior to cleansing and splash the face with cool water after cleansing to constrict the pores. Dilated pores can be easily cleansed and freed of dirt and oil. Constricted pores are less prone to clogging and pimples.
Moisten a washcloth with lukewarm water. Apply a dime-size amount of castor oil to the washcloth. With the washcloth, apply the castor oil to your face with gentle circular motions, focusing on the areas of the face with breakouts.
Allow the castor oil to remain on the skin overnight. According to "Handbook of Dermatology: A Practical Manual," leaving the castor oil on the face overnight lets it adequately moisturize the skin and bind to excess dirt, allowing it to be easily washed away. In the morning, gently cleanse the skin with facial cleanser to wash away the castor oil.