Your genes and hormones play the key role in whether or not you have oily skin. The most important thing you can do for oily skin is to keep your skin clean using warm water and soap, or a soapless cleanser.

Clean your face with astringent pads if frequently washing your face leaves your skin irritated. Use only water-based or oil-free cosmetics if you have oily skin. Diet probably has little, if anything, to do with whether or not you have oily skin.

See also: Acne