Leithe's Cooking while Fishing Guide

Fishing 1-8: Moat Carp
Moat Carps are the most fished in Vana'diel thanks to Lu Shang's Fishing Rod Quest: The Rivalry - The Competition. I'm not going to into great detail on how to find these fish as it's super easy to find information on it. If you're in doubt visit the wiki page for Moat Carp or I've linked my favorite fishing guides at the end. However I am going to recommend using Little Worm as your bait.
Cooking 1-9: Crayfish
You'll mainly be cooking up Peeled Crayfish and Boiled Crayfish with the crayfish you'll be catching with your little worms. 
Fishing 8-11: Bastore Sardine
Switch your bait to Lugworm and keep fishing. 
Cooking 9-11: Bastore Sardine
Slice up your fish into Sliced Sardine. Keep it or sell it, up to you.
Fishing 11-20: Forest Carp
Back to Little Worm and a change of scenery.
Cooking 11-17: Forest Carp
This is only a bridge synth, so don't make any more of these than you have to. I say this because Forest Carp are now allowed to be turned in for The Rivalry - The Competition. Make some Slice of Carp or Roast Carp.
Fishing 20-29: Pipira
Ok if you made Slice of Carp now is the time to use it to find those Pipira.
Cooking 21-29: Pipira and Insect Ball
Use those Pipira you caught to make some Roast Pipira. When you're done with that start on Insect Ball. Yes I know it's not a fish synth per se, but it'll help get those carp biting again.
Fishing 29-37: Shining Trout
Time for another change of scenery, let's get out of town and fish for Shining Trout.
Cooking 29-37: Shining Trout and Bastore Sardine (again)
Fix up some Trout Ball with those trout you've been catching. Then switch over to Fish Broth with our friends the Bastore Sardine again.
Fishing 37-41: Gugru Tuna
Now for some fun on the ferry.
Cooking 37-52: Gugru Tuna and Crayfish (again)
More Fish Broth, I know you're getting tired of it, but push through. When you're done with that switch back to our friends the Crayfish and make them into Crayfish Ball.
Fishing 41-48: Cone Calamary
Still on the ferry, but different fish.
Cooking 52-58: Cone Calamary
If you haven't already, pick up Raw Fish Handling and make some Tentacle Sushi.
Fishing 48-59: Elshimo Newt
Finally off the ferry and not a fish...to fish?
Cooking 58-82: Cheval Salmon and Elshimo Newt
You probably caught a few of these guys while fishing for Shining Trout, time to make Salmon Sushi and some Ikra Gunkan. Alternatively you could make some Herb Quus if you found any while fishing up Bastore Sardine. Then make some Salmon Meuniere with our Cheval Salmon friends before making Blackened Newt using Elshimo Newt. THEN, yes and then: Boiled Tuna Head with any remaining Gugru Tuna you may have.
Fishing 59-