After you have carved away room for your head to fit, and holes for you to breath out of, and don't forget the eyes. Then you can put your chosen fur on the foam block. The fur will make the head larger than the foam block "skeleton" that you cut out. Take this into consideration when making the mouth and eyes. the fure can either be sewn together like a skin, or simple glued on. The skin mothod lasts longer, but is much more work. I used an all purpose spray craft glue, and the head still looks good after almost a year.