Ask a parent or friend to use a measuring tape to find the distance between your fingertips when your arms are outstretched from your sides. Cut a rectangle of fabric that is the length of your wingspan by about 3 feet wide.
Fold the fabric in half lengthwise, then draw three scallops diagonally across the fabric with the marker.
Cut the fabric along the outline, then unfold the fabric and lay it on a flat surface.
Cut 2 3-inch pieces of string or twine. Grab a parent and place a dab of hot glue at the end of one side of the wing.
Twist one of the strings into a loop and secure it to the hot glue. Repeat this step on the other wing with the second string.
Cut 2 triangles from the cardboard, about 2.5 inches wide and 3.5 inches tall.
Paint the triangles black, or cover them in black felt. Then fold the bottom of the triangles to form a base.
ON HALLOWEEN NIGHT
To wear your costume, dress in all black and drape the bat wings against your back, looping the strings around one finger on each hand. Use bobby pins to secure the ears to your hair, or glue them to an old headband.