Size Boo design to 6 inches wide and cut out of Black Iron-on vinyl. If you’ve never used iron-on vinyl read my step by step iron-on vinyl tutorial
Cut a piece of felt so that it fits under the Boo.
Set the Boo aside and sew the felt onto the head band down the middle of the felt.
With a ironing fabric over the Boo design iron it onto the felt.
Pull away the carrier plastic and re-iron through the fabric.
Cut around the design and you’re good to go!