When should one contemplate the application of hyaluronic acid serum in their skincare regimen? Is it most beneficial to employ this remarkable humectant after cleansing, or perhaps following the use of a toner? Moreover, could its efficacy be amplified when layered beneath a moisturizer? Is it wise to apply it in the morning to capitalize on its hydrating prowess throughout the day, or should it be reserved for the nighttime routine to foster rejuvenation during sleep? What about varied skin types—will the timing differ for someone grappling with dryness versus someone with oily or combination skin? And how frequently should it be used to achieve optimal results? Is there a threshold where less is more, or can it be utilized liberally? Additionally, does the method of application, such as gentle patting or massaging, influence its absorption and efficacy? These inquiries beg a thorough evaluation of when to integrate hyaluronic acid serum for maximum benefit.