What safety steps must I follow before and during application, and why is the patch test required every time?

This product is a permanent oxidative dye used millimetres from the eye, so the safety routine is non-negotiable. First, perform a patch test 48 hours before every colouring session: mix a tiny amount of cream and developer, apply a small spot behind the ear or on the inner forearm, leave it for the recommended development time, then rinse. Wait two full days — reactions can be delayed. Do not proceed if you notice redness, itching, swelling, or burning. Even if you have used this exact shade before, sensitisation can develop between uses. Do not use the product at all if you have ever reacted to any hair dye or to black henna tattoos, as cross-reactivity with para-phenylenediamine (PPD) and related compounds is common. During application, wear the supplied gloves, work in a well-lit area, and keep the mixture strictly off the eye itself — if contact occurs, rinse immediately with plenty of lukewarm water and seek medical advice if irritation persists. Apply a thin barrier of petroleum jelly or a rich cream along the orbital bone (not on the lash line) to protect skin from staining. Mix only the amount you need in a non-metallic bowl using the ratio indicated on the packaging; the developer activates the pigment precursors, and the mixture loses potency quickly once combined. Process for the time stated in the leaflet — longer does not mean darker, only a higher risk of skin irritation. After rinsing, avoid oil-based cleansers on the brows and lashes for the first 24 hours to let the colour fully stabilise inside the hair shaft.