There was a thread on Pattern Review about redheads and what colors are flattering. I'm not a real redhead, but I play one in my life so I read it. It turns out, not surprisingly, that not all redheads can wear the same colors. There was also a fair amount of discussion of eyebrows and what to do about them for those of us who get a little help to justify our fiery tempers. I never would have thought of dyeing my eyebrows until I went to get my hair cut several years ago and my hairdresser told me to hang on a minute so she could get the dye off her eyebrows. I figured if a trained professional said it was OK I'd give it a shot. It's great! It makes a huge difference in my face when I remember to dye them, as otherwise my eyebrows are clear (I'm a natural blonde).
**REQUIRED LEGAL DISCLAIMER** I am not a doctor or a cosmetologist. There is a danger from dyeing your eyebrows. Be careful, and dye at your own risk. I am providing this information for free and have no liability for anything you may do. Also, this will only work for dyeing your eyebrows darker; I don't know how to lighten eyebrows.
So here's how you do it.
You can either go to Sally and buy professional products (my choice) or just buy a box from the grocery store. At any rate you need developer, dye, an eyedropper, something to mix on (I use a yogurt lid), some q tips, and some cotton pads or balls.
Developer comes in different numbers and I know they somehow correspond to whether you're dyeing lighter or darker. I just don't know how they correspond. I chose 20 Vol because it's in the middle. It works fine. Make a small puddle on your lid; you really don't need much. It's thick and it helps to use a q tip to get it out.
I have an eyedropper whose sole use is hair dye. I recommend you get one too because it's really hard to pour the right amount. Drop dye into the developer so that they are in equal amounts.
As you can see, I'm a fan of the L'Oreal Mega Reds line. For my eyebrows, I use either light intense copper (shown) or a mix of light intense copper and medium intense golden copper. If you have darker skin you might be able to use a darker color.
Mix up the dye and developer using a qtip until it thickens. It only takes a second. You actually don't need to make as much as I did, I don't know why I mixed up such a big batch. This would have done 3 or 4 pairs of eyebrows. Once the dye and developer have been mixed they lose their potency really quickly, within a couple of hours. So you have to mix up a new batch fresh each time you color.
Here's where technique comes in. Using a q tip, apply the dye to your eyebrows opposite the direction of hair growth, and apply only to hair. Do not get it on your skin. Clean up any that gets on your skin with a q tip. If you are nervous about getting it on your skin, you can put a thin layer of petroleum jelly such as Vaseline on the skin around your eyebrow to create a protective barrier. I don't bother with this, though.
You can see here that while I have loaded the hair generously with dye, it doesn't go all the way down to the roots and touch my skin. Hair dye will color your skin. It fades after a couple of days, but you'll look really funny in the meantime if you don't take precautions.
My fine blonde hairshaft takes 13 minutes to dye. This is about half the time it takes for my whole head to dye (well, took, I've switched to henna for my hair which is 2 1/2 excruciating hours in a plastic shower cap--but the color is so much better and so much less damaging that it's worth it). Don't leave on your eyebrows as long as on your hair--try half at first and see if it's enough. I made the mistake of dying for 25 minutes the first time I tried it. I had cheeto caterpillars on my face.
When your time is up, wipe off the dye first with a dry cotton pad. When you've wiped off as much as you can use a damp cotton pad to clean it up the rest of the way. No need to use soap, but unlike with dyeing your whole head it's ok to wash that day--you don't have to wait three days to wash your face!
Immediately after you remove the dye, they're pretty bright. It will tone down quickly (usually after several hours).
And voila! Matching hair and eyebrows. Nobody will ever know your secret.