Wear all white in a well-lit room with very little or no color. Look in the mirror and assess if your skin looks pink or rosy; if it does, you are cool-toned. If your skin appears golden or yellow, you have a warm complexion. Next, step into the sunlight and examine the veins in your forearms. If they appear blue or purple, you have pink undertones; if they are olive green or yellow, you have yellow undertones.

While there are exceptions to the rule, pink complexions tend to look best in silver, while warm skin tones look best in gold. Additionally, pink toned skin often looks best in white, or vibrant hues like blue, red, pink and purple. On the other hand, yellow skin tones are flattered by colors like cream, brown, orange, yellow, lime and olive green.

People with blue, dark brown, or gray eyes typically have cool complexions, whereas those with amber, green, hazel or light brown eyes often fall into the warm category. Hair can be tricky, because you have to consider your natural tone, not a salon-given color. If your natural hair is very dark brown, blonde, or black, you likely have pink undertones. If your locks are strawberry blonde, red or reddish brown, you likely have yellow tones in your skin.

While it is not a hard and fast rule, people with cool skin tones typically burn in the sun, while those with warm complexions often will tan. After assessing the way your skin reacts to sun, you can then select the appropriate foundation. Those with cool undertones should choose a pink-toned foundation. People with warm undertones should choose a yellow-based foundation. Sometimes you might find yourself wearing a clothing or makeup hue that runs counter to your coloring, but when it comes to foundation, it is best to stay true to your skin tone and choose pink or yellow base makeup accordingly.