Many people agree that a sea robin smaller than 14" or so isn't worth the effort because you won't get a lot of meat but that's your call. The link below shows you a complex way to extract just the meat, rather than our video where it is left to be cooked whole. I've found, however, that you can clean these just like a regular fish - starting your fillet cut just behind the pectoral fin.

http://www.filleting-fish.com/tub-gurnard-sea-robins