Beginner skincare stack — what actually moves the needle?

Tretinoin vs retinol, SPF daily, and what order to apply products.

I've been researching a minimal stack for beginners. SPF every morning is non-negotiable. For actives, I'm leaning tretinoin 0.025% 2–3x/week after building tolerance with retinol. What would you add or cut?

SPF every morning is non-negotiable.

Don't stack too many actives at once. Add one thing every 4 weeks. Niacinamide and azelaic acid play nice with tret if you need extra for texture or redness.

Moisturizer sandwich method saved my barrier when starting tret. Apply moisturizer → tret → moisturizer again. Game changer.