I made sure that my rocks were clean and dry and then I applied modeling paste through select parts of the stencil onto them. I wasn't trying for a perfect impression because that's pretty hard to get on a curved surface. I let the modeling paste dry naturally before I moved on with the project.
I used these stencils: Cherry Blossom, Paris Cathedral, Ocean Waves, Apparatus, Petite Pods, Runes, and Rivermap
Here are the rest of the rocks that I painted.