Lay the cotton rectangle on a flat surface.
Coat the edges in FrayCheck or clear nail polish to prevent the edges from fraying. Allow to dry.
Cut each shoelace in half. You will then have 4 lengths of lace.
Arrange the rectangle so the long sides are horizontal.
Pin one end of a shoelace to the top right-hand corner, pin another shoelace to the top left-hand corner, and pin a third to the bottom left-hand corner. Finally, pin the last shoelace to the bottom right-hand corner.
Thread the sewing needle with a length of blue thread. Knot the end.
Sew the top right-hand corner shoelace into place. Knot the end, clip the excess thread and remove the pin.
Repeat Step 6 and 7 for the other three shoelaces.
Hold the rectangle over your nose and mouth, and tie the top laces and bottom laces together to secure them.