Contouring is an art form, and I see tutorials on how to do it by everyone. What everyone agrees on is that your contour powder needs to be a matte powder, not a shimmery one. After all, shadows are meant to fade into the background, not pop. And a shimmer innately pops to the forefront of the face.
What's not agreed upon is what type of powder to use to contour.
I'm new to the rodeo and admit that I had no idea there was a wrong and right type of powder to use to contour. Every single Youtube beauty guru that I watch just uses their plain old bronzer to contour their face.
And then I watched a video by Jordan Liberty. If you don't know who he is, just google his name. Jordan does incredible faces, and he's the top of the MUA game.
In the video he mentioned his pet peeve - people using bronzer to contour. It was revelatory for me. I had to know more. This is what I've learned through my research:
If you look at your face in a mirror in natural light, all the natural shadows will have a more grey/ashy look to them. Shadows are naturally cooler in tone.
Many a bronzer has an orange undertone to it, so aren’t good for contouring. Bronzer is used for warming up the face. That's it. Why contour with a warmer-toned powder? There's nothing natural about a warm shadow.
The best contouring shades have a greyish or ashy undertone to them. Some examples of good contouring powders would be NYX Blush in Taupe, particularly for fair-to-medium skins. MAC's Eyeshadow in Omega would work also. Physician's Formula has a bronzer with cooler undertones. Ulta's eyeshadow in Sable is a completely matte, gray-toned brown which is just the right contrast for fair skin – it looks very natural, while still giving those awesome editorial-esque cheekbones. Ulta also carries a few other matte browns in the same grey-family if you think you need something darker.
Nyx blush in taupe is a popular contouring powder.