A lot of the aggravation associated with using retinol occurs because it breaks down your skin's protective barrier. As a result, moisturizer will become your best friend, according to Well and Good. But, if you want your retinol to be effective, you must be conscious of the way you order and time the layering of your other serums. Dear Brightly clarifies that moisturizer must be layered on after applying your retinol. Using your moisturizer beforehand can reduce the potency of the product. 

They recommend that you dab the retinol lightly over your skin after washing your face. Then, after applying it, you'll want to wait a moment for the product to soak fully into your skin. In fact, in an interview with Glamour UK, Linda Blahr, a skincare specialist and the Head of National Training at SkinCeuticals, suggested waiting around 30 minutes before applying your moisturizer, or anything else. However, specialists note that you shouldn't use just any moisturizer.