Another pinner said, "Just need a round foam paintbrush - Did this for my bathroom! Used all the grey colors from the walls and a green, pulled from the shower curtain. Super simple and turned out perfect! I would use orange instead of yellow for bedroom
Something like this in the front room. (Different colors) Plywood, Painters tape, and different paint colors. I can't wait to see the look on people's faces when I say, "Yeah, it's just a little something I threw together one day while bored.