I’ve seen this technique a few times out there on the internet, and I’m always drawn to watercolor, so I decided to make a couple cards. I cut out the shapes with freezer paper, which is a wax-backed paper, meant for wrapping food for freezer storage. I can’t imagine anyone uses it for this purpose anymore, what with ziplocks and vacuum sealers. Anyway, cut your shapes out, being sure to have the waxy (shiny) side down, then iron them onto watercolor paper. If you don’t iron enough, the wax doesn’t fully melt, and you end up with paint bleed (see the L in love, below). When the iron melts the wax fully, it blocks out all the paint, and you end up with a lovely negative image.
Here’s the video tutorial which goes into much more detail of how this technique is achieved. Special supplies needed are an iron (of course), Big Shot, and any embellishments to dress it up. Enjoy!