A little bit of color theory

Well Adriana asked for information about undertones so here it is to the best of my understanding. I know her question was about specific products, but I think that before you understand the undertones of lipsticks, it's important to know something about undertones of the skin. If anyone here is a professional and would like to add or correct something, feel free to tell me.

This, my friends, is an exploding color wheel. It's quite an old one and needs to be retired, but it gets the job done.


The way this is organized, all of the primary and secondary colors have white closest to the center of the wheel. The tertiary colors have black near the center of the wheel.
Most of the colors you need to know undertones are going to be in the red-yellow category. All of these are warm colors, but makeup artists will use a finer distinction:
Yellow undertones are cool
Red undertones are warm

If you've ever seen MAC's system which lists NC and NW, the N means "Neutral", C "Cool", and W "Warm". The most popular shades are the neutral cool (yellow/golden undertones) and neutral warm (red/pink undertones). There are some things which fall in the neutral category (one of my favorite foundations happens to fall here). Other brands will have different ways of calculating this, but they all have the same result. If you have a cool foundation, but your skin is much warmer, your foundation will look sort of ashy (the same happens with foundation that is too light). If you have cool skin and your foundation is too warm, you could look kind of burnt. Not tan, burnt. If you are having trouble finding your shade:
1) Get color matched at a makeup counter and if that doesn't work
2) Talk to someone at Perscriptives. They have a very nice system for breaking down different undertones and if premixed colors don't work they can make a custom foundation for you (it's not going to be cheap though).

Another thing to look at on the color wheel: Find the orange and go to the lighter colors. You will find peachy colors there. Now staying within orange, go to the darker colors. You will find two browns before you hit the black stripe. The point of saying this, is that these generalizations of coloring in respect to warmth and coolness are applicable to different levels of pigmentation.

It is very possible that you have several undertones in different parts of your face. The inside of my face is generally NC where as my forehead and around my hairline warms up to N. The gradation is smooth enough that I like it and I keep it when I apply makeup by using two powders and blending them together. In the summer I usually use a warmer foundation (mostly all N), and in the winter if I don't get much sun exposure, I use more of the NC. But sometimes there are smaller coloration variations that some people might want to minimize before putting on foundation for a more even color. Now here is where we look at the other colors on the wheel.

Just like a color wheel without tertiary colors, this is arranged in such a way that you get complementary colors directly across from color you want. So find the red (at 9:00) and then find its complement at 3:00. I haven't worked on the tertiary ratios, but as far as primary and secondary, here are the groupings:
1 yellow: 3 purple
1 orange: 2 blue
1 red: 1 green

Now there are fun things that you can do with this in painting, like split complement work, but there is an advantage to knowing this for makeup. You want to go with the complementary color of the problem area to minimize it's visibility before applying your foundation. MakeUpForEver (MUFE) has a concealer section of the website where they show different concealer palates for different skin tones and warmths. That should give you an idea of the conventional colors used for different ranges.