If I had to pinpoint a time when contouring became popular, I would have to say it was with the rise of the Kardashians.
I personally never feel comfortable with that amount of makeup on so my approach to contouring is a lot more subtle. Some people will use bronzer to contour but bronzer is for adding warmth. It lacks the gray tones that imitate natural shadows.
It is generally suggested that you create a 3 shape, using a contour color- starting at the center of your forehead, moving to the middle of your ear and along the contour of your cheek, go back to the ear and continue along the jaw line. I also go on both sides of my nose to add more dimension to my flat nose.
Then highlight along the cheekbones, center of the forehead and down the center of the nose, cupids bow and chin.
My favorite two products are:
Becca Lowlight/Highlight Perfecting Palette ($42) - a natural shadowing cream and a luminizer cream. The contour color is the perfect mix of brown and gray to be very natural. Both formulas are somewhat sheer so you'd really have to cake it on to mess it up. The luminizer reminds me of RMS Living Luminizer but more golden.
Smashbox Step-By-Step Contour Kit ($45) - a trio of powders: a bronzer, a contour, and a highlighter. There's a handy little sticker on the mirror that instructs you on how to use each color. It also comes with a small angled brush. I really like the bronzer and contour but I'm not crazy about the highlighter.
It would be really difficult for me to choose between the two. But if pressed I guess it would be the Becca because the highlighter and contour are both amazing.