The general idea behind this technique is to use an enemy to take damage and get pushed halfway through an object like a fence. (Or you can also use a well placed Big Bomb, as seen in the video further down.) From there, if you use the Hookshot, its chain will appear glitched, following a strange trajectory, making it possible to grab on to things at a weird angle.
The setup required to get in position for the technique varies depending on multiple things, such as the thing you want to clip through (corner, straight fence, etc.) and the enemy used.
A version of the Hookshot clipping is used to perform Rosso's Ore Mine Skip.