Finding a good foundation, powder..., anything base makeup; can be much easier to find when you know your undertones.
Normally, there are two undertones that are classified in the makeup world:
warm- yellow
cool-pink
And if you know which one really is YOU, then it'll be easier finding foundation, powder...etc. , that TRULY match with your skin tone, and make you glow even more. So here are some easy 'tests' that can help determine which undertone you are.
VEIN TEST
Look at the veins in your wrist/hand..etc. If they are... :
-More blue: COOL (pink)
-More green: WARM (yellow)
SUN EXPOSURE
What happens when you go out in the sun without sunscreen?
-Burn easily: (probably) COOL (pink)
-Tan easily: (probably) WARM (yellow)
GOLD OR SILVER
Try putting anything gold on you. Whether it be a liner, a bracelet, necklace...etc. Now put something silver to it. Which one looks better on you, and which ones give it a certain 'glow'?
-Gold : (probably) WARM (yellow)
-Silver: (probably) COOL (pink)
What does this mean?
Now that you know your undertone, it can help find the kind of colors and shades that will flatter you best.
If you are COOL (PINK)
Foundation- try to find a foundation with pink undertones. (in mac it's the NW collection)
Eyeshadow- cool, jewel tones would probably look best on you like; blues, violets, greens...etc.
Blush- a nice rosy, pink blush :)
If you are WARM (YELLOW)
Foundation: try finding a foundation with a rich yellow (olive/brown..etc) base. (in mac it's the NC collection)
(you have a yellow undertone, but does your foundation have a pinkish undertone...(maybe) making you look too white, pale, or ashy? no worries...it's fixable. Click here:
Eyeshadow: A lot of earth tones and metals. Like gold, burnt red, browns, copper...etc.
Blush: try staying to peachy (try coral if your tanner)...it'll look amazing :)
Here is also another really good chart I found on the web.
hope this helps, and take care :)