Need to use dye based inks for this technique. I colored the butterfly stamp with dye ink markers.
Next, spray the inked stamp with water, the ink will start to bead up on the stamp.
Stamp the image on the paper (I think it's better to use non coated paper).
You can continue to re mist the stamp with water, without re-inking it (Julia states you can do this up to 3 times).
This second stamping has a great watercolor effect:
And I re misted the stamp and stamped it again. This image is very faint, but would make a great background:
You'll get different effects depending on how much ink you use on the stamp and how much water you spray on the stamp.