Most hair colors fall into either 'warm' or 'cool' families. If you better with gold jewelry, you are in the gold type. Gold types are more suited to warmer colors.  If you have golden, olive or dark skin and brown or dark eyes (most Latinas, Asians and African Americans fall into this category).  You tan easily and the veins in your inner wrists are green. If you feel you look better in silver jewelry, you are a silver type. For Silver types, the color choices are cool tones. You're a 'cool' if you have fair skin and blue or green eyes. You burn before you tan and the veins in your wrists run blue. If you're confused because you sometimes burn, sometimes tan, you likely skew warm.

Important note:  If you are naturally a light blonde you probably don't want to suddenly change to a dark color or it will look abnormal.  It is usually best to stay within 4 levels of your natural shade, which still offers you a wide range of color choices.  If for some reason you feel that determining your color type is too difficult, or you are unsure of your type, simply take a hand-held mirror and stand outside in direct sunlight.  Look closely at your hair as the sun is shining on it. Look for the underlying base color that reflects off of your hair.

If you see glints of red, orange or gold (yellow) you can choose hair colors with those base colors and feel safe. If the color glinting off your hair is bluish, purplish or greenish you will want to choose hair colors with the blue, violet, or neutral base colors.

People who had blonde hair as children have the right skin tone to be blonde adults.  

Almost everyone can go red, what's most important is finding the right shade to complement your skin color. Women with a cool or pink skin tone pull off red best.