Lay an old sweater out and cut off the bottom. Now there will be a loop so cut off a rectangle that will fit around your head. Measure around your head and cut off the excess. Split it into thirds or fourths and cut an arch shape. With the fabric inside out, glue or sew one half of the arch to the other half and continue until the whole top is closed. Then glue or sew up the side. Flip it right side in.
