Separating shaft and cv

Ok I've scoured the internet, watched several CV/swivel overhaul videos, and I'm struggling to find anyone who goes into detail about how to separate the half shaft from the CV joint (300tdi). I've seen some people talking about tapping gently with a hammer, but I'm not sure what I'm supposed to be tapping.

And again when I'm putting my new one on, I've seen people saying "tap with hammer, be careful not to damage pin"... What does that mean!?

Why the hell couldn't I find that!?

Thanks!

No worries. I had the same concern when i did mine.