At the time, the "in" thing was to use mineral spirits and either Q-tips or blender stumps to shade images. Once I was introduced to Promarkers, the pencils got put away and forgotten.
There was a short video posted on Facebook recently with instructions on using colored pencils to shade stamped images that already had the shadows incorporated in the image. I decided to give it a try.
Using the pencils adds just enough color to the image to make it stand out. I used a Strathmore toned gray sketch book for the base and mounted it onto some Bazzil gray cardstock.
I like the effect the pencils give to the image. It's more delicate than using a marker and takes only a few seconds to complete.