Eyes
Natural eye makeup is usually one or two shades, placed so the lid looks awake. A natural smokey eye is a brown or taupe wash with a soft edge, not a black ring. Easy natural eye makeup for everyday is mascara plus a pencil pressed into the lash line and smudged until you cannot see a drawing.
A natural cat eye, if you want one, is a short wing that follows your eye shape and stops before it becomes graphic. Blue eyes often need a warm brown more than a blue shadow. Green and hazel eyes can take a soft plum or bronze in a very small dose. Brown eyes look clear with a matte taupe and a clean lash. None of these require matching the iris like a costume.