Put it at the end of a tumble sequence, after the slip and just before the reaction shot. Open a bigger fall with the Bass Drop Sound, then let this clip close the sequence, and follow it with the Fail Sound Meme for the punchline.
Über diesen Sound
This is a very short, low cartoon body-fall thud lasting less than half a second, with a deep bassy impact that lands all at once. It feels sudden and comic, like a pratfall caught mid-collapse. The clip comes from the 1948 Pluto cartoon Cat Nap Pluto.