does it really matter if you apply moisturizer before serum? Or if your SPF goes on last?
YES. layering incorrectly can prevent products from working properly and render them ineffective. for example, applying a cream before a serum would create a barrier, not allowing the serum to penetrate into the skin. the rule of thumb is to always apply thinnest to thickest *remember to save you active ingredients (i.e. retinol, AHAs, BHAs, etc) for nighttime* if you use an oil, always save it for last as they create a barrier on top of the skin to seal & lock in ingredients