Wash squid under cool running water. Peel off the outer mottled skin. Pull the head and viscera from the body. (If the transparent quill bone comes out easily, the squid is very fresh.) Collect the thin, elongated ink sacs and set them aside in a small cup. Remove the tentacles by cutting just below the eyes, then turn the head over and press out the tough round beak. Discard the beak, the viscera, and the transparent quill bone. Rinse the inside of the body well. Leave the pouch whole for stuffing. Store the pouch and tentacles in a small amount of icy water until you are ready to cook them.