How do I prepare and apply the paste for the most even result?

Use a non-metallic bowl and spoon. Add warm (not boiling) water gradually while stirring until the paste reaches the thickness of yogurt or thick cream — thin enough to spread easily, thick enough not to drip. Let it sit for 5–10 minutes after mixing; this allows the indigo to begin releasing pigment. Apply to clean, towel-damp hair (no conditioner or oil beforehand, as they can create a barrier). Section the hair and work methodically from roots to ends, saturating each strand. Wear gloves and protect clothing and surfaces; indigo stains permanently. Cover with a shower cap or plastic wrap and a towel to retain warmth, which helps pigment uptake. Processing time controls depth: 30–60 minutes for a subtle cool tone, 90–120 minutes for maximum darkness. Rinse thoroughly with water only; avoid shampoo for 24–48 hours while the colour fully oxidises and sets.