What preparation and safety steps should I take before using this permanent cream hair dye?

Permanent oxidative dyes contain paraphenylenediamine (PPD) or related sensitizers that can cause allergic reactions even after years of uneventful use. Perform the skin allergy test exactly as described in the leaflet: apply a small amount of mixed color behind the ear or on the inner forearm, leave 48 hours uncovered, and watch for redness, itching, swelling, or burning. Do this before every application, not just the first. Do not wash hair for 24–48 hours before coloring; natural sebum protects the scalp from irritation. Wear the gloves provided, cover shoulders with an old towel or cape, and apply a barrier cream or petroleum jelly along the hairline, ears, and nape to prevent skin staining. Mix the color and developer in a non-metallic bowl using the ratio stated on the package (typically 1:1). Use immediately — the mixture loses potency after 30–45 minutes. Section dry, unwashed hair into four quadrants. Apply first to regrowth if touching up roots, then pull through to ends only for the last 10–15 minutes of processing if the length needs refreshing. Rinse with lukewarm water until it runs clear, then use the post-color conditioner or mask included in the kit. Wait 48 hours before shampooing again to let the cuticle fully close and lock in pigment.