One common method for moistening Henna tattoos is mixing lemon juice and white sugar and applying it to the Henna design, which helps the Henna tattoo last longer and stain darker.
Furthermore, how long does henna last on hands?
Hereof, how do you preserve henna on your skin?
Heat helps intensify the stain, so keep your skin warm while the paste is on and through the first 24 hours. In the cooler months I like to cover the design with tissue and then place a heating pad over it for a few minutes at a time. A space heater works well too, but try to avoid drying out the henna too much.