The pack contains 25 g of powdered henna. How far that goes depends on your hair: short or fine hair needs less paste, while thick, long or very dense hair may require more than one pack for full, even coverage. If you are only refreshing a small area, testing a strand, or working on short hair, you may not need to prepare the entire contents at once.
Because this product is a dry powder, you can mix it fresh before use. Put the amount you need into a non-metal bowl and gradually add warm water until you get a paste that can spread through hair without dripping. Add liquid slowly; a paste that is too runny is harder to control and more likely to stain skin, clothing or surfaces. Prepare enough to coat the hair generously, because patchy application can lead to patchy colour.
Apply to clean hair in sections, especially if your hair is thick. After processing, rinse thoroughly until the water runs clearer and avoid using light-coloured towels immediately afterward. Store any unused dry powder tightly closed in a cool, dry place, away from moisture. Do not store mixed paste for routine later use unless you are specifically following a reliable henna method, as water changes the powder from a stable dry product into a prepared colouring mixture.