Cut two strips of the bandana about 10.2 cm (4") wide. Sew the two strips together end to end.
Fold the right sides together and stitch the length of the fabric so you end up with a tube. Turn the tube inside out.
Measure and cut the length of elastic you will need to fit around your pet's neck without being too tight.
Attach a large safety pin to the elastic and thread it through the tube.
Stitch the ends of the elastic together.
Pull one side of the tube over the other to completely cover the elastic.
Stitch on the buttons and the charm to the front of the collar.