Luttes everyone has their favorite way, don’t change it if your guests plates are bare 
Here’s my method, it’s really easy but has a few very important parts to it.
Starting off with the fillets themselves, I never cook them whole unless they are smaller panfish.
On bigger panfish I “unzip” them into two halves. For walleyes, I “unzip” them and cut into fingers. The bigger the fish, the more fingers I cut.
In the summer (especially) I soak all of the meat in milk, a half hour minimum, up to overnight. It helps to get rid of any fishy/weedy/muddy/summer taste. It’s not completely necessary, but it does make a difference.
Next, if you like things a little spicier, soak the meat in some hot sauce prior to breading. Smaller/thinner fish don’t need much, thicker/bigger pieces can take a lot more. Give it a few minutes minimum, and up to 10 minutes or so. If you go longer, the color of the sauce gets into the fillets and it looks funny eating orange meat lol
Now onto the breading. I cook fish with all sorts of different things, but as mentioned my favorite is Fried Chicken mix. Shorelunch makes a good one, but literally any brand works just as well.
I leave the fingers wet, whether it’s from water, milk or hot sauce. You want some moisture to get dry breading to stick. It’s the complete opposite if you are using a wet batter, then you want to pat the fillets somewhat dry.
The next step makes a HUGE difference when using dry batter.
After you roll/shake/pat/Batter Pro or whatever in dry mix, LET THEM SIT before dropping them into oil.
You want most/all of the dry batter to start looking “wet”. This makes for a far better finished product, because the breading will stay on the fish and not fall off into the oil. Their texture will be more like a chicken finger from a restaurant.
Next, fry the fish in 350-375 like normal. Cook the fish longer than it “needs to” without getting it too dark. If using a wet beer batter, err on the lower side (350), or they brown too fast.
A lot of people complain about fried fish being oily, when in reality it’s just too much moisture. Soggy fish is bad fish. Don’t be afraid to cook the hell out the meat, especially with thicker pieces.
Once you see the amount of steam escaping from the meat slow way down, you’ll know they’re done. The pieces will all be floating too.
Don’t be afraid to experiment, cook a round like normal, then intentionally overcook a round. See what texture you and your guests prefer.
Next is a trick I learned years ago and makes a big difference too. Instead of placing the cooked fish on paper towels, invest in a handful of cooling racks (like for baking cookies). This allows any drips of oil to fall down, instead of the meat sitting on a soaked paper towel. I also use the cooling racks when I’m letting the dry mix turn wet-looking prior to frying. It’s far less surface area for the breading to stick to.
I’ve cooked a ton of fish in my life, and wish I knew 25 years ago what I know now 
Along with using cooling racks, I highly recommend a Batter Pro for applying dry mix. It’s so much easier, cleaner, and faster than other methods. Both are money well spent.
