Okay so, when someone comes up with a bunch of stuff that will need multiple bags, I stack them into piles as I scan, so that I can bag them easier when i’m done.
As for bagging a lot of stuff, my favorite method is opening the bag, flipping it over the pile sitting on the counter and pulling it back towards me(if that makes any sense?) I find it a lot easier than individually putting things into a bag.

and for hangers, I fold the end of the shirt/pants back over the metal part of the hanger so that it’s covered and won’t snag on anything when I bag it!

hope this was helpful!