Lay your sheet of corkboard on a flat work surface. Run a tape measure against the bottom edge, measuring out 80 inches. Run the tape measure against one side, measuring out at least 47 inches.
Cut the headboard to this rectangular shape with the dimensions you've measured by using a jig saw.
Measure a sheet of foam to the matching dimensions of the headboard and cut it out with an electric knife. Spray the cork board with a spray adhesive and press the foam against it.
Measure out a piece of batting the is 3 inches longer in the width and length. Press the batting against the foam, pulling the sides of the batting back and stapling them to the back of the headboard. Repeat this process with a soft piece of fabric, such as velvet or flannel. Your headboard is now ready for hanging.