Sgraffito Doodle

I saw this wonderful piece of art on the internet the other day where someone had tried a technique called Sgraffito. The traditonal method is incising plaster I believe, but there was a more modern day approach for scratching into wet paint, so that is what I tried. I had to work pretty fast, as I didn't really use the right product ... I needed an acrylic retarder, so my paint wouldn't dry too fast.