Size the Boo design to 3 inches wide in Cricut Design Studio and cut the Boo out of Iron-on glitter vinyl making sure to mirror image the design. If you’ve never used iron-on vinyl read my step by step iron-on vinyl tutorial
Through a thin piece of fabric Iron the glitter design onto the felt. Pull away the carrier plastic. Iron again through the fabric.
Cut around the glitter design.
Cut a small piece of felt and slide in between the bobby pin.
Apply hot glue to the straight side of the bobby pin and glue the pin and felt to the cut out boo piece and you’re good to go!