After the henna has been applied & bandaged it's best to leave the paste on for as long as possible, preferably 8-10 hours to get the darkest stain. The longer the paste is left on, the darker the stain & the longer it will last. Once the paste is dry, however, it's no longer active & should be removed.
When you're ready, remove the bandage & this should pull off most of the paste with it. Apply olive oil (or any edible oil) to a paper towel to assist in removing any leftover residue. The oil will then help to protect the stain from water when you rinse it, which is the next step. After rinsing, pat dry gently...the henna stain is most delicate at this time.
Initially, the color will be bright orange & much lighter than the final stain. Don't worry, it will darken up over the next 24 hours, generally turning a deep red or reddish-orange. The final color of the stain depends on your individual skin type, where on your body the henna was applied, how long you leave it on, & how well you care for it afterward.
Try to keep it as dry as possible the first 24 hours to allow for maximum darkening. Any kind of oil or salve (not containing petroleum products) can be applied to the stain as often as desired & can help to repel water when you bathe or swim. Olive oil, coconut oil, cocoa butter, shea butter, salves made with beeswax, lip balms, anything natural. Chlorine is always damaging to the henna. The more you protect your design, the longer it can last!