You can either remove the bones from your fish before or after cooking it. It's actually a lot easier to remove them once the fish is cooked but it's generally not very pleasant to eat fish that has had the bones left in it.

The first step is to clean and rinse the fish thoroughly. That is, the fish needs to be gutted and rinsed in cold running tap water. Then place the fish on its side on a clean cutting surface. Using a sharp knife, cut straight down into the fish, just behind the gills until the blade touches the backbone. Then rotate the knife so that the blade is laying flat against the backbone, parallel to the cutting surface. The sharp edge should be toward the tail. Using a gentle back-and-forth sawing motion, cut along the backbone all the way down the fish to the tail, under the fillet. Repeat the same for the other side after turning the fish over. Now the backbone has been removed and the ribs and pin bones need to be removed next. Just cut the rib cage bones away from the fillet by slicing between them and the meat of the fillet. Remove the tiny pin bones by pulling them out with a pair of needle-nose pliers or tweezers. If they are not visible, feel for the tips of the bones with your fingers.

Always be sure to use care when dealing with sharp knives. Dull knives should not be used, as the blade will have a tendency to tear the fillet and not cleanly slice through it. Using a serrated or electric knife on fish will also shred the meat.