There are many factors that go into having good skin. First of all, watching what you eat is highly important, and so is creating an appropriate barrier between it and the natural elements. This needs to be thick enough to provide adequate complexion, but also thin and breathable at the same time.
Interior hydration is also essential, which is why people with amazing complexions are usually those that drink at least two liters of water daily, if not more. But, of course, the products you buy and put on your face and body also make a difference. This is why you need to cater to your specific skin type and its needs.