If you want to beautify your skin, first protect it with nicotinamide, and then moisturize it with glycolic acid. Niacinamide can even out the skin tone, shrink pores, and strengthen the bottom of the skin, which is very useful. When the skin is suitable for nicotinamide nourishment, then apply glycolic acid. Glycolic acid can exfoliate, promote metabolism, and rejuvenate the face. The two are combined, and the skin is radiant and radiant. Then it should be used with caution. According to the nature of the skin, gradually increase its agent to prevent the skin from being intolerant and injured. In this way, the beautiful skin can be expected.