Cocoa butter, as the name implies, is a product derived from the cocoa bean. According to Joyofbaking.com, cocoa butter is a byproduct of the process of making chocolate and cocoa powder. (See Reference 1) This product has food uses but is also used in lotions and cosmetics because it moisturizes skin, making it very soft and supple. You can buy and use pure cocoa butter, which comes in bars or tubs like dairy butter, to use directly on very dry skin.
Cleanse your face with a warm, damp wash cloth and a facial cleanser that will rinse clean. The warmth will open your pores and the cleanser will remove dirt; together, these prepare your face for the cocoa butter. Don't dry your face; the cocoa butter works better if applied to damp skin.
Pull your hair back away from your face using hair ties and/or bobby pins. Cocoa butter won't hurt your hair, but it will make it greasy if it touches the product.
Open the container of pure cocoa butter. Scoop about a dime- to nickel-sized amount in your hand. Cocoa butter is semi-solid but will start to soften right away in your hands and you won't need to use much product unless your skin is exceptionally dry. Let it soften and melt partially by simply holding it in your hand.
Rub the cocoa butter over your face, starting at the driest areas, where you will want to use the most product. If your skin is combination oily/dry skin, simply avoid rubbing the cocoa butter on these oily areas.
Keep rubbing the product into the dry areas of your face until your skin has absorbed it. It may feel slightly greasy for a short while, but that is normal, and it will gradually sink into the skin more. If you want to speed up the process, wet your wash cloth in very warm water and press it (don't rub or you'll rub some of the cocoa butter off) against your face.