How to fillet and pin-bone a fish:
Cut into the fish behind the gills and fin cutting at an angle until you reach the back bone:
Starting just behind the head, cut the fish down the length of its back just along the side of the back bone
Work down again from the head keeping the knife flat and running it over the top of the bones pulling the fillet back as you go.
Now cut the fillet free and turn the fish over and repeat the process but start from the tail up to the head
Now with both fillets free you can start by pin boning them using tweezers. Run your finger over the fillet and you will feel the line of bones, simply pull each one out. a good tip is have a small bowl beside you with water in it to get rid of the bones.