Using a utility knife, cut a 14-by-18-inch piece of homosote. Cut the oilcloth at least 2 inches wider than the board (the length of the oilcloth should be at least 1 foot longer than the board's width, depending on how many pocket folds you want to make).
Starting about 8 inches from the bottom, pull the oilcloth upward until you make a 3-inch fold; it should resemble an upside-down Roman shade. (It's a good idea to do this with a ruler nearby, so you can make sure the folds are perfectly even.) After each fold, secure a binder clip on each side to hold the fold in place. When you've made all the pocket folds you want, make sure you have at least 2 inches on the top and bottom to fold in back.
To attach it, lay the oilcloth on your work surface with the pocket folds facing down. Place the homosote board, centered, on top. Starting with the sides, remove the binder clips, and pull the oilcloth taught. Using a staple gun, staple the oilcloth onto the board; repeat on other side. Staple the top or the bottom in the same manner, pulling the oilcloth tightly; fold the corners as if you were wrapping a present. For the back, cut one more piece of oilcloth just slightly smaller than the board. Using the staple gun, secure the piece onto the back to cover the exposed homosote for a neat, finished look.
Both easy to make and easy to clean, this clever board makes an ideal receptacle for outgoing mail and important notes. You can simply tack it onto an ordinary bulletin board, attach it to the fridge, or casually lay it out on the kitchen counter.