Serum, retinol, acids: the order that avoids irritation

Layering is mostly about thickness and timing. Thin, water-based products go first; rich creams go last. Strong actives get their own evening rather than sharing one.

The morning order

Cleanser, firming serum, moisturiser, SPF. Nothing else is needed. Sunscreen is the single most effective anti-ageing step in the routine, so never trade it for another serum.

The evening order

Cleanser, firming serum, then either a retinoid or an exfoliating acid — never both. Finish with moisturiser to buffer the active.

A workable week

Monday and Thursday retinoid, Saturday acid, every other evening serum plus moisturiser only. If skin feels tight or looks flushed, drop one active evening rather than stopping everything.

Signs you are overdoing it

Stinging on application, a shiny tight surface, small flakes around the nose. Pull back to serum and moisturiser for five days; the barrier recovers quickly.