Highlights are bright and contours are dark. Use bronzer or darker eyeshadows (in the crease) to create depth or contour, and use illuminators, highlighting pencils, etc. to brighten up the face for the highlight areas. It will make a huge difference!
This is simple yet an effective way to use highlighter. Now remember were talking highlighter, not contouring! I want to remind you that less is more very easy to overdo.dont fret, wash off begin again!