So it's time for me to start working on my first guide ever! The main point of this guide is barbarian fishing is ftw! To be clear right off the get-go, I'm not talking about barehanded fishing, I'm talking about barbarian rod fishing. So, let's get this guide going!
Firstly, the requirements.
70 Fishing (This is so you can catch the sturgeon)
45 Strength (Also so you can catch sturgeon)
45 Agility (Err...Also so you can catch sturgeon

)
Barbarian Fishing Rod...To fish with...Hope that's obvious.
25 Feathers to get you started
Knife to cut up the fish
Games Necklace to get there (there of course being barbarian outpost).
What you'll be catching...
Leaping Trout - 50 fishing xp, 5 agility xp, 5 strength xp, and if you get roe from it, 10 cooking xp.
Leaping Salmon - 70 fishing xp, 6 agility xp, 6 strength xp, and you will always get roe from salmon, so 10 cooking xp.
Leaping Sturgeon - 80 fishing xp, 7 agility xp, 7 strength xp, and you will always get caviar from sturgeon, so 15 cooking xp.
This gets me to my first point about why barbarian fishing is so good! You get xp in
4 skills!!!
Now the method.
1. First, teleport to the barbarian outpost and run south to the hut where you learn all the barbarian methods.
2. Next, fish from one of the spots near the hut.
3. After you have a full load (25) cut up all the fish. I start with Trout to know how much room I'm going to have. Then I do Salmon and Sturgeon, but it's up to you how you want to do this. Also, there is a "cut all" option, so you don't have to click each individual fish.
4. You should, after cutting up the fish, have an inventory consisting of Roe, Caviar, and Offcuts. THESE ALL CAN BE USED AS BAIT!!!!!!!!!!!!
5. Before the next step, there is an order in which bait is used. It goes offcuts, roe, then caviar. So, for the next step, fish some more. If you have more offcuts than free inventory space, drop the extra offcuts when you fill your inventory. Proceed then to fish the rest of your inventory (using Roe and Caviar) until it is once again full.
6. Repeat steps 3-5 repeatedly until 99 fishing is achieved. Along with significant gains in 3 other skills, 99 fishing, from level 70, just cost you 25 feathers, and you did it faster than monkfish fishers could possibly dream of.
To put the extra xp gained into perspective, were you to start this method at level 70, you would need 12.29M xp to get to level 99. Along the way, you would gain 1.229M agility xp, 1.229M strength xp, and approximately 2M cooking xp (the cooking xp is a rough estimate). Now, 1.229M xp is enough to gain any level...even from 98 to 99.
In very real numbers, from my current stats, I will have gained 12 Agility levels (65-77), 1 strength level (97-98), and quite a few cooking levels (83-??) by the time I hit level 99.
And almost anyone you talk to will say this is the best method out there, better than fly fishing and dropping in Shiloh even (although I haven't done a test on this yet, but I will). Although, there will be some debate about barbarian fishing and dropping, but that sort of defeats the purpose of the fish being their own bait if you ask me. And it's much more expensive cuz you need to buy all the feathers (or time consuming if you kill chickens for the feathers

).
XP Gained
I did a 1 hour trial doing this and I gained the following amounts of xp
Fishing - 40,130
Cooking - 5,900
Strength - 3,656
Agility - 3,656
These are not inflated numbers I promise you! My current levels are 81 Fishing, 83 Cooking (not sure if level has anything to do with xp gained using this method), 97 Strength (you can say it, I'm a beast

), and 65 Agility (you can say it, I'm a noob

)
This is opposed to another 1 hour trial doing monkfish in which I gained 30,360 xp.
Now, you may say...it's only a 10k xp difference. But fishing monks you get approximately 250 fish per hour, which is approximately 85k gp. But! In 2 hours, I will be 20k xp ahead of you, 3 hours 30k, and 10 hours 100k. Not to mention in 10 hours I will also be 59k cooking, 36k strength, and 36k agility ahead of you (training-wise at least). And, I can pretty much guarantee you that while you're gaining that extra 210k total xp, I will have made more than 850k gp.
This is a great method and I would recommend that all of you at least give this a try. Do the same test I did (1 hour at barb fishing, 1 hour at other method of your choice) and get your own proof that this is fastest!
P.S. This being my first guide, comments and feedback would be GREATLY appreciated. Oh, and I plan on updating with some pics, just haven't gotten around to it yet.
Credits go to ME for writing the guide and doing the XP tests.
Axeraider194 for first telling me about this method.
And, Tip.it where I got the information on xp/fish.
F.A.Q.
Q. Where can I get another Barbarian Fishing Rod?!?!
A. So, if you don't have a Barbarian Fishing Rod, but have completed the Barbarian Fishing part of Barbarian Training, the fishing rod is under the bed of the guy who lives in the hut.