Many women already have natural shadowing on and around the eyes, so subtle is better. In fact, if you're wearing eyeliner and mascara, you might not need any shadow at all. Don't go with anything too shimmery, and look to matte, silk, satin, and velvet formulas. If you want to achieve a smoky eye, neutrals are better than dark or bright colors. You should also avoid tones that are too earthy as they could come off as muddy.