FACIAL OILS VS. SERUMS: CONFUSED YET? | How are you supposed to know what to do and how to use your products? How do you layer? Does your oil replace your serum? What the hell is a serum-oil… or is it oil-serum? There’s a ton of mixed information out there, a lot of inconsistent answers. I’ve done my research, I’ve asked skincare reps and professionals. Today, we’re breaking it down so we can all know w.t.h. we’re supposed to do.