Tape the paper to keep it from curling, then spray with water and wipe off the excess water.
Firmly press a bold image stamp into dye based ink to get it well inked, then stamp onto the watercolor paper.
Lift off the stamp and immediately spray with water. Julia says to spray just once and the pressure from applying the water will move the paint into the webbing patterns.
I'm not sure if I've used the wrong type of watercolor paper, or the hot sun is drying my paper too fast or my spray bottle is too fine of a mist. I sprayed a couple of times: