Use the back of the knife to scrape off the scales from both sides of the fish.

Next, insert the knife from the anal vent, which is right below the caudal fin, and slice up to the head to remove the guts.

Cut off the head once you have removed the guts.

Make shallow cuts along both sides of the dorsal fin.

Cut along the lateral line in the middle of the body.

From that cut, slice along the spine to remove the flesh. Move the knife along little by little to cleanly.

There you have one fillet. Now, all you have to do is repeat.

Fillet the other half, and now you have three pieces.

Flip the fish over and repeat the above steps. Now you have 5 pieces.

Finally, insert the knife between the flesh and skin, pulling on the skin to fillet completely. Hold one end of the skin, and slice off along the skin.

You're finished.