Dye your hair first with henna.

When you've rinsed out the henna, you dye over that with natural indigo.

Mix indigo with water and stir it up.  The indigo paste should be as thick as stirred up yogurt, though it will be very lumpy like porridge. It will be a green mush that smells like frozen peas.

Lay plenty of newspapers, or a tarp, on the floor where you'll apply the indigo.  Indigo will stain linoleum and cloth.  Wear plastic gloves or your hands will have grey-blue stains. 

Section your hair.

Immediately after you stir water into the indigo, put it into a squeeze bottle to squish it into the hair, or just slather it in by the handful.  Work it down to the scalp, and mush it in like you're trying to plaster a wall with guacamole.  Try to get indigo evenly into all the hair.  It's messy.  It's stinky.  Remember that women believed the uglier they got with their beauty preparations, the lovelier they'd be when they were done.

Wrap the indigo-laden hair with plastic wrap into a great mooshy sloppy peas-smelling turban and let it stay there half an hour.  Wipe all the indigo drops off as they dribble down the neck, forehead and back!  These will leave gray streaks if you don't wipe them away!

Rinse this all out of your hair.  It takes about a day for the indigo to oxidize completely, and then your hair will be amazing black!

How much indigo do you need?
If your hair is short, 100g will do.  If your hair is straight and comes to your collar, 200g should do. If your hair is straight and comes to your shoulders, 300g should do.  If it's waist length, try 500g.  Gwyn has very curly hair that stretches to mid back, and her hair is very thick.  It took 500g to do her hair.
 

Don't do this is you want to dye blonde highlights into your hair later.  

Don't do this if you can't stand a mess or if you're in your parent's house and they can't stand a mess.

Don't do this if you don't have a friend to help you.

It's best to do this if you have brown hair to start with!  If you're a blonde, redhead, or light brunette, harvest hair from your hairbrush and try henna and indigo on that to see how it'll come out.  Once the indigo is in your hair, it's there for a long time!  Make sure you like it before you go for it!

If you've dyed or bleached your hair in the previous year, harvest hair from your hairbrush and try henna and indigo on that to see how it'll come out.  Once the indigo is in your hair, it's there for a long time!  Make sure you like it before you go for it!

Don't do this if you like to change your hair color frequently.  This is a commitment.  Once you do your hair with indigo, you'll have to keep doing it with indigo or let it completely grow out. 

What's indigo going to do to your hair?  Will it be wonderful?  Will it suck?  Harvest hair from your hair brush and try some!  Want samples of henna and indigo and other hair goodies so you can try stuff?  Go here!