What guidelines should be followed in choosing a hair color shade?

For a natural look, choose a shade that is one or two levels from your natural hair color. Consider your skin tone and eye color and the color your hair was when you were a child. Hair color with warm tones, i.e., red, gold and auburn shades, tend to be more compatible with warm skin tones. Cooler-tone colors, i.e., lighter gold or ash, are more suitable to fair skinned or sallow skin tones. Make a subtle change first. You can always go more daring the next time!