Use whatever wood/material you would like. You can scale the images, as well, but make sure to scale them both the same.

The backing piece is one solid piece, but the top layer will need to have a gap between each piece you keep. You can see from my final image that I removed every other piece. If you start from the outer-most ring, it'll be much easier.

I didn't with this particular squiggle, but I like the look of painting the rings and the back piece sometimes. I also like it without paint, so take your pick!

I found it easiest to start with the outer-most ring and go inward, gluing each ring with a gap between it and the next most large ring.