Since several people asked me how I do paintings similar to "Tomato Juice" - watercolor on Yupo with wax crayon as a resist - I gave up and made a video. Actually, i made three videos but only two of them with the camera on and only one where the painting is close enough so you can see what's going on. The result is one video and three paintings :) The video:
(sorry it's so small - I recorded it in vertical format :/. I promise I will know better next time)
And the paintings:
The first and last ones have oil pastels as resists.