Cut two identical pieces of cotton material into 21-inch by 17-inch rectangles.
Lay the rectangle with the right sides of the fabric together and the wrong side on the outside.

Sew all around the edge of the rectangles, ¼ inch from the edge. Leave a 5-inch space un-sewn.

Turn the pillowcase inside out, bringing the right side of the pillow case to the outside.

Fill the pillow case with the buckwheat hulls so that it is full, but not so packed that the hulls cannot move about.

Hand sew the 5-inch hole with the needle and thread in small, tight stitches so that no hulls can escape.

Alternatively, a simpler method is to put buckwheat hulls into a high thread-count pillow case and sew it close.

You can clean the pillow by hanging it outside to air out. Beat the pillow to loosen any dust particles.

Alternatively, open a 4 inch hole in the stitching at one end of the pillow, empty out the hulls into a container. Wash the pillow casing, dry it and refill it with the hulls carefully. Re-stitch the opening in the pillow casing.