Patch test first on a small area (like your jaw or behind your ear) before using it on your full face. Next, apply only at night on clean, dry skin after cleansing and toning. Then, smooth a thin layer of moisturizer first if you’re new to retinal or have sensitive skin. After that, dispense 1–2 pea-sized drops of retinal serum and spread a light, even layer over your face, avoiding the eye and lip area. Finally, follow with another layer of moisturizer to reduce dryness and irritation. Finally, begin 2–3 times a week, then slowly increase to nightly use once your skin adjusts. Finally, wear sunscreen every morning because retinal makes skin more sun-sensitive. Finally, tIP: Avoid using retinal right after laser treatments, physical scrubs, or chemical peels. Finally, mild flaking, redness, or irritation can happen at first, this is normal while skin adjusts. Do not combine with strong acids like AHA or BHA in the same routine.