Next I took a strip of balsa trim that I bought at a craft store. It is 1/4 inch wide. Balsa wood is excellent because you can cut it fairly easily with a razor blade or exacto knife. I cut 2 pieces 2 inches long and glued them to opposite sides of the board. Then I lay the trim across the 3rd and 4th sides and marked with a a pencil where the cut should go. I used the razor blade to cut an angle where the two sides meet.
To finish up I glued a square of green felt to the bottom to hide the bottom.
Finally, I glued the pieces to the board. A more realistic checker board would have some loose pieces on the side that have been captured. I don't think my children will be able to keep track of tiny loose microscopic checkers so I glued everything down.