I don't have a bell but I call "ring ding a ring ding" and generally get a laugh. I go past at a sensible speed, say thank you and that's it done. I think that there's a legal requirement for some sort of audible warning on a bike, but as I have a voice that will do.A bell on a road bike is completely useless. I used to have one on a mountain bike as I was using shared trails, I found people hated the sound of it so ended up just saying “excuse me”. I tend to give a verbal warning of coming up behind a horse rider.
It’s just common sense & courtesy.