Building a skin-care routine isn’t easy, especially when you’re not sure how long to try a product before you know if it works for you. See how long you should give it to start seeing if it works. Also, how long it should take depending on what it is. Experts in the skincare industry, including Amy Peterson, weigh in on all aspects of knowing if your routine is working including what to do if it still isn’t working, and when to start seeing a professional.








