Mehendi paste on skin is the whole point - but on clothes, sheets, or upholstery, it's a stain you want gone as fast as possible, and the approach that works changes a lot depending on how fresh the stain is. For a fresh, wet mehendi stain, act immediately: scrape off as much excess paste as possible with a blunt edge (don't rub it, which pushes the dye deeper into the fabric), then rinse the reverse side of the stain under cold running water to push the paste out rather than through the fabric. Never use hot water on a fresh henna stain - heat sets the dye, making it far harder to remove later. Once excess paste is off, treat the area with a paste of liquid detergent and a small amount of lemon juice, gently worked in with an old toothbrush, then left for 15-20 minutes before washing as normal. For white or light-colored cotton fabrics, a diluted hydrogen peroxide solution (mixed with water, never applied full-strength) can help lift residual staining that detergent alone doesn't fully clear. For dried or set-in mehendi stains, soak the item in a mixture of warm water and oxygen-based bleach (the color-safe kind, not chlorine bleach) for at least an hour before washing - chlorine bleach can react unpredictably with henna dye and sometimes sets an orange discoloration instead of removing it, so it's worth avoiding on anything you actually want to save. Delicate fabrics like silk or fine cotton need gentler handling - skip the toothbrush scrubbing entirely and instead blot repeatedly with a mild soap solution, taking the item to a professional dry cleaner if the stain is on an expensive or heirloom garment rather than risking DIY treatment. The most effective prevention is simply covering clothing during the mehendi application itself - many artists provide a cloth or plastic sheet to protect clothes and surroundings, and it's worth asking for one if it isn't offered, especially for light-colored outfits worn to the ceremony itself.