What you needPolymere beads / Water Wise Beads (found at garden centers for water retaining)
Tight weave fabric
Cut a rectangle 35 x 4 1/2 inches (88 cm x 12 cm).
Mark the material at both 7 inches (17 cm) and 9 1/2 inches (24 cm) from the short ends. These ends are used as ties.
Finish the raw edges from one 9 1/2-inch mark around the point, to the other 9 1/2-inch mark with an overclocked hem.
Fold the rectangle wrong sides together and sew along the long sides, between the 7-inch marks, using a small stitch and around 1/4 inch seam allowance.
Turn right side out and sew a double row of small stitches across one end at the 7-inch mark.
Place 1 to 2 teaspoons polymer beads in and sew across other end at 7-inch mark, making sure there are no gaps.
To use soak in cold water and wear.