How do you use a cell phone properly?

I dunno if anyone has yet set out rules of etiquette for using a Cellphone correctly,but not using it when you may be putting yourself or others at risk should be at the top of the list..(I'm looking at You,Drivers..) Putting the thing on silent mode when you're in a meeting or eating out should be up there too.. And answering it in those same situations only to have a loud conversation with the person on the other end while behaving as though those seated around you didn't exist would be another no-no..take the call outside where you can have some privacy!