For this you have to know that what type of makeup foundation good for your skin. If you have oily skin then you have to apply powder form foundation, that it merges into your face skin and make a medium combination skin.
If you have dry skin then you have to apply the oily foundation based on your face to make it medium and nice look. Then you have to match the color of foundation with your skin color. If it has dark complexion then you have to apply a little bit lighter tone to your skin and if you have fair color then you have apply the color according to your face color.
Because the objective of the foundation is make face look better and perfect look to face, as we want. Always apply water proof based foundation of your face, because when you go out, specially in summer then it will become melt down and then face of your become worst not give good look.
So take care all these things you will surly find the perfect face look as you want.