Do I *have* to actually push, can’t I just concentrate on screaming?

[Snacks]

TBH I was happy just hanging on and screaming

If that was effective, go with it
Is there anything about 2nd stage of your last births that you wanted to change? Are you worried about being rude? Are you wanting things to go faster or slower?
If not, then just roll with it. It's a third baby and will therefore probably just slip out while you are having a cup of tea. PMSL! Of course I'm joking, but I think the mw's will likely just tell you to do whatever the heck you want (within reason, LOL. No hair-pulling or name-calling ok? Keep it moderately clean please, Rach) because your body is pretty darn good at this now.

[~Lashes~]

if screaming worked for you, and you were comfy with it, go for it!!
i remember trying to push thinking it would happen faster with my first 3, only to be told off and not to push till they said, pfft whatever, ill push when i feel the need to, ok!!