Take your rod & bait, and take a boat out about 50-100 feet from shore, where it is still shallow, but where you can still visably see fish. Cast only about 3 or 4 meters tops. Fish will swarm to it, and you won't get bothered by mob spawns. I have caught at least 150+ fish this way (the chunky purple ones) that give 4 fish each. Didn't even have food buff, but did have rested buff, so you can fish on an empty stomach and still catch heaps of fish.

Fish in clear water so you can see them. A fish will make a run at your bait and its pretty easy to time setting the hook. I also keep around 10 meters out to be sure stamina is not an issue reeling it in.

I just wait till the fish is right in-between my hook and me, and then quickly pull the hook back towards me so the fish gets stuck and pulled back as well. It works for me that way lol

You Throw the bait in the area where you can see them some 10 meters far. then you keep on pulling meters by meters until the bait cross the area where you can see them. Most of the time one fish will be interested. Then when get hooked you pull til half stamina. At half you go in land and keep pulling.

Fish don't steal your bait. If you don't snag them, you just wait for another pass. You fish in visible conditions where you can see them making a run for the hook. And when you see the bob, or them get really close, hold the button, don't tap it. If they grab it while the button is pressed they'll become hooked.
This is all advice coming from someone (me) with significant nerve damage with laughable fine motor skills much of the time, so I can assure you none of it requires "twitch shooter levels of unreal" reflexes. Fishing is one of the activities I do when I'm having an extra bad function day and can't engage in combat.
Without actually seeing you fishing I'm unable to give any more specific advice.

Moving slowly in a boat with your bait dangling in the water allows you to auto catch them.

Most vikings fished with nets, just saying,

Fish chased my hook/bait up on land while a wave was in and water high- then the water level dropped, the fish flopped around, and I went and picked up the fish.

Can try occasionally reeling your line in a little at a time, stop, reel in more, stop- set the hook like that on more than a few fish without trying.

Originally posted by psiic:

Most vikings fished with nets, just saying,

Yea wish they set up seining or trolling from a boat. Be nice if the Ocean biome was full of Tuna!

It takes a bit to get the timing right but eventually you can tell when a fish is interested. You right click just before they get to it and it will snag them. Sometimes they come darting on a mission from 10 meters away , this is when you know you have a fish , again just before it hits the hook. I can consistently pull stacks out of the ocean standing on my dock.