Step one: Be rank 14 and get a fishing rod.
Step two: Buy a RIVER lure for one gold bar. You can also buy worms but the worms cost $0.50 each and eat into your profits.
Step three: Go to the Dakota River at night. Walk along the shoreline with your lantern, and look for the salmon that glow bright red under your lantern light. Try to find a big group of them at a very narrow part of the river, and they need to be close to shore.
Step four: Drop your line right in front of them. They will bite almost immediately, and because they are right along shore there is almost no reel in time (this part is crucial). It should only take a few minutes to catch all 10. I even one time had a group of 3 of them follow my line and they "beached" themselves on a sandbar and died. I could pick them up.
Step five: After you got all 10, take a 2 minute horse ride to strawberry and sell them to the butcher for $42.50. then go back to your fishing spot, cast one time and reel in, and all the fish will soon respawn there.
Step six: if you see a guy fishing along the Dakota river with a horse named carrot, don't shoot him.
Edit: You buy the river lure with a gold bar from a real vendor, not the catalog. If you try to buy it from the catalog it will say locked until level 30. The reason for river lure is so that you only get the salmon and not the smaller fish there. I prefer the salmon over the steelhead because they are bright red and easy to spot from the shore.
© Post "How I make $300+ per hour in online. Played all day and have nearly $2800 on hand. Even better than steelhead fishing." for game Red Dead Redemption 2.