Basically, you buy silk mesh. I use a fine one (100 mesh) like this:
https://www.amazon.com/Yards-Screen-Printing-Fabric-Count/dp/B00G43RSQG/ref=mp_s_a_1_4?crid=3C8FFMLO43QXV&keywords=silk+mesh&qid=1706990044&sprefix=slik+mesh,aps,186&sr=8-4
Cut it to the shape of the earcups but size it so there's a bit of overlap w the clips around the driver.
Place it over the driver and clips and snap in the earpads. Easy peasy.
If you don't have some overlap over the clips, the mesh will move around or fall out, as there's nothing there to keep it in place. The trick is to cut the mesh to a size that fits over the clips enough but isn't so big it hangs outside of the earcup once the earpads are snapped back on.
Here's some picks. Good luck to those who try this. It's a super simple mod
Clips circled
Only thing w this mod to note is you lose a bit of cup space as the mesh kind of hovers a few millimeters over the diaphragm. It's not a drastic difference and the sound is improved so I hardly mind.
It's not just that lol. See above. I've done a version of this on my 6 series headphones btw