Dark green is a good color for redheads to wear because red and green are complementary colors. If the hair has some blond in it and is closer to orange, light blue is also a good color.
Color plays an important part in clothing choices, and it is generally one of the first things people notice. Certain colors naturally complement each other. On a color wheel, complementary colors are directly across from each other, which is a good way to use the wheel to remember which basic color will match well when paired with another color. The reason why complementary colors are pleasing to the eye is because they contrast well, but in an aesthetic way. This vibrant contrast causes clothing and other apparel to stand out.
Colors in clothing can also play a big role in determining moods and how others will perceive the wearer. The color red is often associated with danger and passion, and easily captures attention. A red dress is a good way to stand out and give off a seductive mood. Likewise, black is a color that represents authority, so a black suit would give a person a powerful appearance. Green and blue are calming colors and have soothing effects that serve especially well to balance out red hair.