The dimensions worked really well with their twin beds.
First I covered the canvas with batting from the fabric store.
Then I covered it with a linen fabric (you could also use a painters dropcloth)
To finish it off I added some nailhead trim in a nickel finish. It came in a package of 10yds. which was plenty for two twin headboards. You can buy it HERE:
And here's the headboard:
For the complete room tour go HERE