How-to Remove Skin from a Fillet
Use a sharp flexible knife to remove the skin from a fillet. Position the fillet with the tail end closest to you. Starting at the tail end of the fillet, make a small 45° angle cut in the meat to, but not through, the skin. Using that cut as a starting point, insert knife and angle it flat against the skin.
Hold the skin taut with one hand and slide the knife along the skin, separating the skin from the fillet. As you push the knife away from you, pull skin toward you.