I love messing around with acrylic paints, and make a lot of my card backgrounds with them.
I usually thin the paint out a bit then smoosh it on the cardstock. You can use an old credit card to move the paint around, as well as combs and other household items. I usually just sponge mine on.
The stamp is from The Angel Company, and is stamped on glossy cardstock that has had alcohol ink applied. I tore the edges. I used the polka dot ribbon and the buckle to add a little interest. This ended up being a birthday card for my brother-in-law.
Have a happy day.