How do I prepare and apply this henna powder correctly for the best and safest result? — Iranian natural henna, 25 g

Start by doing a skin patch test 24-48 hours before use: mix a small amount of powder with hot water, apply a dab to your inner elbow or behind the ear, and rinse after 30 minutes. Check for any redness or itching. If clear, proceed with application. Wear gloves and old clothing, as henna can stain skin and fabrics.

To prepare, pour the 25g powder into a non-metallic bowl. Gradually add hot (about 70°C/160°F) water while stirring until you get a thick, smooth paste with a yogurt-like consistency. Let the paste sit covered for 30-60 minutes; this 'dye release' period allows the color molecules to activate. Apply to clean, dry, product-free hair, section by section, from roots to ends, ensuring full coverage. Once applied, cover your hair with a shower cap and leave it on for 1-4 hours depending on the depth of color you want (longer time gives more intense results). Rinse thoroughly with warm water until it runs clear, then shampoo gently if needed. The color will continue to develop and deepen over the next 24-48 hours.