Dye them. You can have it done professionally, or you can do it yourself. If you dye your own hair, just wipe a little color along your brow about 5 minutes before your hair is done, and hop in the shower to rinse. Of course, the box advises against it, because you could probably get dye in your eyes and go blind, but the odds of that happening are pretty low. I've done it 100 times. If you were contacts it would be advisable to remove them first. Because the little baby hairs around the actual brow will be dyed too, make sure that they are recently plucked or waxed. My skin is too sensitive to both wax and dye on the same day, so you may want to give it a few days inbetween.
If that is too extreme for you, use powder to make them darker. I find it more foolproof than pencil. Pencil done wrong looks like little old ladies that draw them dark enough for their old eyes to see.
Man I wish I could make mine lighter! But um there's this powder cream like thingy made by that New York Co (they have it at Target) its like 3 bucks, it worked well for my sister. It comes with a little special brush to put it on with too.
kaykay -- I think they only come in like 3 shades, so you shouldn't have to go darker. I have dark blonde brows, and I use the "blonde" color, and it is definitely much darker than my brows.
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