Pushpins on foamboard. Trace your design first, buy twice as many pins as you think you'll need. If framing, cut foam board to frame first. - Cute way to use the push pins I bought for my DIY headboard and didn't end up using.
This might be great as an accent wall behind a bed - in two colors - white lines and color over. Modern Wall Art I just completed my most favorite DIY project. My tween just got a cool new wall treatment with +FrogTape and a few colors of paint.