Undertones?

Ask for beauty advice just about anywhere and someone will ask you, "what are your undertones?" If you shrug and say you don't know? They're going to look at you like you forgot your birthday. Like you misplaced the card we're all secretly handed at puberty that tells you how to suavely get dates and what the difference between white and black tie is that had your undertones marked down on it.

What, you didn't get one of those? Me either. 

So, then comes the parade of advice on how to pick your undertones:
The color of your veins (check your arms, folks:) blue means cool, green means warm (red means see a doctor)
Jewelry: like silver you may be cool, like gold you may be warm
Clothing: look good in blue? Cool, they say! Pink or orange? Warm it is!
White-test: Put on a pure white shirt (or hold up paper under your face) - yellow and sick-looking? Warm! Just fine? Cool!

Now, the next two "tests" lead to mis-matched undertones all the time, because they assume that dark=warm and pale=pink and everyone in between is cool. I know some un-cool people in that middle range and I'm not just talking social skills. These tests have lead to a lot of people telling me I must be warm because blah blah blah: Tan easily? Have certain hair or eye colors? Then they stick you in a category.

What happens when you're a blue-green veined pale person with no pink who likes silver, looks good in blue, looks terrible in a white t-shirt, burns easily, has a naturally dishwater shade of hair, and gray eyes? Oh, you're neutral. Huh, no one seems to mention that during these infuriating tests. I've had counter representatives refuse to match me to a non-pink shade of foundation because "all pale people are pink!" No, no we aren't.

Then you'll get advice on what kind of colors you "should" be wearing.

Funny thing, I look best in red, purple, and blue.

In green, yellow, and orange I look like I need a vacation or a doctor.

Here's the thing - you can wear any color you want to. The place that undertones are going to make the biggest difference is in foundation. There's an additional wrinkle here, many companies will say a foundation is "for" someone with cool undertones when what they mean is that it "corrects" cool undertones. That's not cool at all. Knowing that you're cool undertoned, though, means that you can usually skip foundations that all have yellow undertones or if you're warm you know that you can skip the ones that all have a reference to pink in the name. You'll know what that online foundation-finder means when it says "cool-undertones; medium shade."

Another place it's going to make a difference is picking a great shade of red lipstick - blue-reds (those touted as "universal" - you'll learn I dislike anything being proclaimed as "universal," you're undoubtedly making someone feel like a mutant for not fitting the shade) are going to look best on cool undertoned folks, orange-reds and corals are going to look best on warm undertoned folks, and us lucky neutral-toned folks are going to have a hit-and-miss toss up of which works best. (I think this is where the "universal" comes in, as many neutral-toned people do better with cool-toned color cosmetics or at least like them better.)

In short, no you didn't miss that day at school and half of the people who think they've got it figured out have no idea, either. It doesn't make a huge difference but it might make finding a foundation easier if you can figure it out and it'll be one more thing you can stick in the introductory sentence to your request for assistance that lets you skip to the answers that you want. :)