To use niacinamide, simply add it to your skincare routine in place of your regular serum or moisturizer. You can also find best niacinamide serum in India in many face masks and sheet masks. Leave the mask on for the recommended time and then rinse it off with warm water. https://medium.com/@olismith1012/how-to-use-niacinamide-for-natural-clear-skin-8c4482b3c497