Layer a frame on a painted board
Vintage Superman Comic Decoupage Picture Frame by junksy on Etsy... not a DIY.
Stick-on decals. Put on a picture frame, just don't add the back to the frame - genius!! Would be cute with quotes too!
DIY Repurposed Towel - The Sunbathing Companion - 35 Summery DIY Projects And Activities For The Best Summer Ever