How exactly do I use this two-step serum and mask, and how often can I use it? — Snail age restoreal multi-stage procedure 1 sheet + snail serum

This product is designed as two steps: the ampoule serum goes on first, then the sheet mask. The serum layer is meant to prepare the skin and help it take up the mask ingredients; the close-fitting 3D mask then holds the formula against the skin and slows evaporation, which makes the active ingredients more noticeable than a plain serum.

Before starting, remove makeup and cleanse the face so the serum can make direct contact with skin. Apply the serum ampoule in a thin, even layer over the face, and optionally the neck. Then unfold the sheet mask and place it over the face, smoothing from the centre outwards around the nose, cheeks and chin. The 3D shape is intended to sit more snugly over facial contours than a flat cloth mask, but small adjustments are normal.

Leave the mask on for the time printed on the packaging. A practical guideline is to remove it before the sheet starts to dry, because a dry mask can pull moisture back out of the skin. After removal, gently pat or massage the leftover serum/essence into the skin. Rinsing is not usually necessary unless the residue feels sticky. Dry skin will benefit from a moisturiser or cream afterwards, since a hydrating mask works better when the moisture is sealed in.

As for frequency, this is an occasional treatment rather than a daily step. For dull, dry or mature skin, once or twice a week is a sensible starting point, adjusted based on how your skin reacts. If your skin is sensitive, has active breakouts or reacts easily to acids or active formulas, test the serum on a small area before full application and do not apply the mask to visible irritation. If you are pregnant, breastfeeding, have a chronic skin condition, or are using prescription skincare or medication, consult a specialist before using a product with active ingredients.