As you can see my counter says that I have 2570 items hooked.

Go to your world and take any items you have (the more you have, the better)
In my case it's 10 stacks of planks (200 items)
You can use more items, but be careful because the game may start to stutter!

Drop your items into the water like I did.
Use the right mouse button to grab 1 item and drag it from your eq.
(drop by 1 item, not by 1 stack)

Now fill all your eq with items that won't stack with the stuff you just dropped.
(For example leaves)


(This way you won't have to manually drop items every time you hook them.)

Now hook items.

As you can see my counter went from 2570 to 2770, which means that I hooked 200 items at one throw.


Repeat it untill you get achievement.