how do you do the jumping glitch lol

jump twice in a row really fast buddy.

This doesn't work all the time and it pisses me off, I click jump super fast and it still doesn't do it all the time, how is the world record possible... (PC)

listen to the runs when people double jump, if you listen to the spacing between the jump sounds that's the timing you have to jump. It's about 10-12 frames if that helps you

Yeah. It's not just a matter of hitting jump twice as fast as you can; there's a precise timing to it.

Just keep practicing and eventually it will just click; you'll start to get it much more consistently.

You also have to release the jump button after 1 frame