Note: Because of my geographic region and time of year, I will be using a Tilapia. The cleaning of other fish may be more difficult or incur specific changes. For example, cleaning a Northern is much more difficult due to the amount and placement of their bones.
Step 1: Gather Materials
* Fillet Knife
* Cutting board (at least the length of the fish; double the length will work best)
* Bowl of Cold water
WARNING: The use of a sharp knife is dangerous, but a dull knife is even more dangerous. Make sure your knife is sharp and follow proper knife safety (http://busycooks.about.com/od/howtocook/a/kitchenknife_2.htm); always keep fingers out of the projection of the knife.
Step 2: Separate the Spine from the Fillet
a. Lay the fish on its side with the spine facing you.
b. Place your knife at a 45 degree angle, under the fin, at the point where the gills meet the body of the fish.
c. Make a downward cut that is about 1/2 of an inch deep or half the width of the fish. This cut should reach from the spine to the belly.
Step 3: Separate the Spine and Ribcage from the Fillet
a. Place your knife at the point that your first cut meets the spine of the fish.
b. Make a horizontal cut as close as you can get to the spine while still ensuring there are no bones in the fillet. The cut should go from the gills until just before the tail and only go through half the height of the fish.
**Note that this might not be one fluid cut. You will need to pay attention to where the bones are and move slowly.
**Make sure that you do not cut the fillet off the tail yet.
c. After you separate the spine you will spread the cut open so that you can see the spine.
d. Now that you can see into the center of the fish, you can locate the ribcage and separate it from the fillet.
Step 4: Separate the Stomach from the Fillet
a. Flip the fish so that the cut side is still facing up, but the stomach is now facing you, instead of the spine.
b. Cut through the fish in the same manner as Step 3, avoiding the stomach and guts.
**Use your first cut as a guide to wear the spine and rib cage are located.
**Make sure you still cut above the spine and ribs.
**When you get to the bottom of the fish, be careful not to cut through the tail just like in Step 3.
c. Peal the fillet away from the gills like you are opening a book, with the tail acting as the binding. The head and body should be on your left side and the fillet should be on your right.
Step 5: Separate the Fillet from the Skin
a. Before you cut anything yet, carefully place your knife at the tail of the fish so that you will be able to make a horizontal cut the fish from the tail to the end of the fillet.
b. Without cutting through the skin of the fish, make a horizontal cut as close to the skin as possible.
**This may take more than one fluid cut depending on your skill level, but when finished you should have the fillet completely separated from the fish, with no bones or skins attached.
CAUTION: Sometimes you might have bits of skin attached. If this occurs, simply cut or peel the bits of skin off.
Step 6: Repeat
a. Flip the fish over and repeat all steps in order to separate the second fillet from the fish.
b. Repeat all steps again for any additional fish.
DANGER: If camping, make sure to follow campground regulations when disposing of fish remains. Failure to due so could attract animals, such as bears, and result in injury or death.
The more practice you get, the better feel you will get for the anatomy of a fish. This will allow you to make more precise cuts, attain more meat from the fish, and go through the process quicker. No matter how long it takes you or how "pretty" your fillet looks however, freshly caught and cooked fish is a taste that is incomparable to buying fillets from the market.