An easy way to find the general areas is to look at yourself in a mirror in bright, natural light, tip your chin down slightly and see where the shadows appear on your face that you want to deepen. Depending on your features good places to deepen the shadows are under the cheekbones, along the jawline, down the sides of the nose and around the edges of your hairline. Use your fingers, a makeup sponge or a brush to blend the contour until you get an effective and seamless look that works best for you.
Apply highlighter anywhere light naturally reflects, another way to look at it is apply it to the high points of your face - the brow bone, the tops of your cheekbones, the cupid’s bow, down the bridge of the nose, and the tip of your nose. Work with your face shape to find what works best for you.