Brown eyes come in many different shades so let’s look at a kaleidoscope of colors to help us to enhance eye color. Colors opposite each other will be complementary so, will work to brighten each other up. For example: Red and green, orange and blue, purple and yellow. Depending on the shade of brown your eyes are will determine the shades of eye shadow you may use to brighten the brown which, may give you the effect of lightening that you are after, especially if you use colors that shimmer. If your eyes have a yellow tinge, try using an eye shadow with a purple tone.
The next thing you need to consider is the one rule of makeup that will always guide you: Light colors bring out, make larger and highlight. Dark colors recede, minimize or contour. So with this in mind you could work with dark eyeliner and light eye shadow colors to emphasize your dark chocolate eyes with black liner, mascara, a smudge of pale pink eye shadow, and finish with lightly flushed cheeks and make your lips your signature. Create lip focus with a red or berry stain. To pull color focus from your eyes, giving the illusion of lighter eyes, go for a deeper shade of lip color.
Dark...