Tagging on to the point about not ringing the bell. I can honestly not recall how many years it is since I had to do that. If I would like something, I normally wait until a member of c/c is passing down the aisle, unless they look very busy or are obviously engaged in something else.
If I am in the aisle seat, then I might wander to the galley and ask for it there. I get exercise and they have one less boing of the bell.