Stamp an outline image on shimmery white cardstock using white craft ink (or other embossing ink) and emboss with white embossing powder.
I wanted to use my embossing folder so after running the shimmery white through my big shot I brayered ink lightly on top then embossed with white embossing powder. With the brayer I was able to apply ink only to the raised lines.
Spritz with water so you have puddles between the lines. Pick up some reinker on the tip of an aqua painter and touch it to one of the puddles and watch it spread. Keep doing this until you get the look you want. Make sure you let your paper dry good before you mount it on a card as it will warp your card stock if you get impatient (ask me how I know that).