Henna stains the skin in a very predictable, chemistry type of way. A good stain relies on many different factors. Some things will be beyond your control, ph balance, general health but there are many thing you can do to allow your stain to become as dark as possible.
1. Buy the best Henna you can!
Cheep Henna will provide cheep stains! Any Henna powder sitting on a shelf will not be nearly as good as Henna bought from a good supplier. Premade Henna cones bought at the Indian markets are JUNK. They contain chemicals, smell horrible, can burn the skin and give bad stains. Do not fall into the trap that Indian Grocery Stores will have the best Henna because they are Indian!
Henna stains the best on hands, feet, arms & legs.
Necks, backs, bellys, chests, faces do not stain as well.
3. Proper prepping
Skin should be cleaned, most artists use alchohol. Lotions, oil should be removed.
Some people insist on rubbing oil ( mehndi or lavender) into the skin befor doing Henna for a darker stain. This is counterproductive! Henna needs a good clean bond directly to the skin for the darkest stain!
4. Plenty of time on the skin
Skin loses it's ability to asorb Henna after 8 hours of direct contact. So, keeping Henna paste on for 3 days will not give you a better stain. We recomend keeping paste on for at least 4 hours on hot days to 8 hours on colder days.
5. Stay warm
This is very important! If you have cold hands or feet, wrap up after getting Henna. Henna grows in the dessert, it can not grow at all in colder climates. We keep Henna in freezers to prevent the paste and powders from losing it's dye, so it only makes sense that cold limbs will inhibit the stain process.
6. Avoid water
This is crucial! After you scrape off the Henna paste, avoid getting the area wet for as long as possible (24 hours is optimal.) Water will wash away the top thin layer of Henna that is left behine after removing the paste. This top layer is key to awsume stains, so no water!
If you must shower you can apply a light coat of veggie or EVOO to the stain, but it will compromise the stain slightly.
Do NOT apply any petrolium products! They will prevent the stain from developing fully.
Do NOT swim! Water is bad, chorinated water is worse!
7. Time to develope
Henna stains darken by drawing in oxygen. It takes 24-48 hours for a stain to fully develope after the paste is removed. Give it time before you think your henna has failed.
Imagine a banana turning brown, or apple slices turning brown, it is the very same oxidation process Henna goes through. A slight wash with lemon juice and water will stop an apple from turning brown, Henna can be just as finicky.
Good luck with your Henna. Like anything, things worth having take time and effort and a bit of planning in advance.