Below is a picture depicting locations to put highlights and low lights.
Below is a picture from Kevin's book Face Forward. First off I feel like to really understand contouring you need to realize shading will cause receding and highlighting will bring forward. With that in mind learn your facial structure. Feel your bone structure and work from there. Different highlighting and contouring will cause different looks.
Contouring is a technique that helps the face recreate natural shadows. You can use one tone/shade of foundation with a bronzer and highlighter or you can use two shades of foundation. Two levels in color is appropriate for everyday use.
Our faces have natural areas that create light and dark shadows. When we put on foundation (all one shade) we eliminate these shadows creating the “floating head” look. This look is eliminated by adding the shadows back in with darker and lighter colors. This is an essential step in creating a polished look, specially for special events such as weddings and other engagements.
When contouring choose a darker color that isn't highly reflective. This will cause light reflecting pigments to be where one would want depth.
Highlights on the other hand can be shiny because we want them to reflect light. Looking at the picture you can see the dark places that should recede and the light places should come forward. Below are pictures of beautifully contoured and blended out faces. Keep in mind, the picture above is demonstrating an overly dramatic version of contouring.
Tyra with contouring makeup & without.
Below is a stage makeup effect of contouring and highlighting. You can see that when done properly it can make a dramatic youthful slimming effect or an aging fattening effect. You can manipulate contouring to elude different results that you want based on your desired look.
Other Kevin Aucoin books worth purchasing!