I used a piece of 142 pound watercolor paper and scrunched it up (a similar process to crumpling) while it was dry. I un-scrunched it, flattened it as much as I could while taping it to a heavy board. I scraped the width of a piece of charcoal over the folds to highlight them. I wet the paper and painted in sections with blues, quinacridone oranges, transparent irons and yellows.
After the paper dried, it looked like a mountain range. It was three dimensional, puffing out of the 2-D plane.
Here is a picture of this study lit from the side:
Below is a more evenly lit picture of the same study: