Completing the co-op game How to Fish requires a loop of fishing, managing your hunger, and defeating bosses to progress across five distinct islands. To succeed, you must prioritize buying the Extra Inventory Slot on each new island and using the most effective lures available to maximize your income.

Island 1: Basics and the Spider Crab

  1. Buy the Crab-Fishing Rod, catch crustaceans, and feed them to the lighthouse keeper for cash.
  2. Purchase and upgrade your knife.
  3. Feed a can of beer to the lighthouse keeper and take the empty can he returns.
  4. Use the empty can as bait to catch the Spider Crab boss.
  5. Feed the crab's shell to the keeper to receive boat keys.
  6. Buy the radar tablet for $10 and follow the green dot to island 2.

Island 2: Trickshots and the Giant Piranha

  1. Purchase a Fishing Rod and use dynamite to catch multiple fish simultaneously.
  2. Upgrade your shotgun.
  3. Collect three leeches and feed them to the woman on the island to receive Leech Bait.
  4. Equip the Leech Bait to catch the Giant Piranha boss.
  5. Feed the Piranha Skeleton to the woman to update your radar with the yellow dot.
  6. Buy the Big Motor upgrade and sail to island 3.

Island 3: Desert Island and the Pufferfish

  1. Upgrade your SMG—keep this weapon for future islands.
  2. Buy a Standard Boss Lure to catch and kill the Blue Shark miniboss.
  3. Feed the shark to the grill master to obtain a lighter for his grill.
  4. Catch an "endangered" fish (Needlefish, Bowlfish, or Seahorses) to trade for carrot bait.
  5. Use the carrot bait to catch the Pufferfish boss.
  6. Feed the Pufferfish Fin to the tourist to unlock the coordinates for island 4 (red dot).

Island 4: The Albatross Boss

  1. Upgrade your sniper rifle and SMG.
  2. Use a Professional Boss Lure to catch and kill a Tuna.
  3. Place the dead Tuna on the grassy patch to summon the Albatross boss.
  4. Defeat the Albatross and give its head to the shopkeeper to get the location for island 5 (magenta dot).

Island 5: The Final Boss

  1. Upgrade your assault rifle and sniper rifle; you can now sell your SMG.
  2. Catch five fish and trade them to the scientist for Fish Bucket bait.
  3. Use the bait to catch the Bowhead Whale boss.
  4. Defeat the whale, pick up the corpse, and carry it to the volcano summit.
  5. Throw the whale into the volcano to summon the Mutated Bowhead Whale.
  6. Kill the Mutated Bowhead Whale, feed the fin to the scientist, and take the keys to the black boat to finish the game.