Different types of foundations work with different skin types, so decide whether your skin is more oily or dry before picking a foundation. If your face is always shiny, you breakout easily, and you tend to have larger pores, you probably have oily skin. If your face has rough or red patches, barely visible pores, or flaking skin, you probably have dry skin. If your face has parts that seem oily and other parts that seem dry, you have combination skin.  If you have oily skin with larger pores you should use a matte foundation to help dry up your skin’s natural oils. Girls with dry skin should moisturize first, and then use a creamy foundation rather than a matte one. This will keep your skin moisturized and looking fresh. If you have combination skin, you should pick a foundation that will give you your desired end effect. Sometimes dark skinned girls have a difficult time finding the right color foundation because many girls are naturally two toned and have a complex color. The best way to find the perfect foundation is to use several different colors together to match your skin. You might find that your skin is lighter towards the center of your face and darker towards the outer edges. Using two different colors on the different parts of your face and then blending them together where they meet will help you get a very natural look with foundation.

TL;DR in Chinese:
使用适合自身皮肤类型的粉底。 找到最合适的粉底色号。