Generally, we use (name) + san, it's the most common. Before you know her/his name, you can say あなた. For "I", saying WATASHI is natural, sometimes boys/men say BOKU but girls/women generally don't.
Please remember that OMAE sounds really rude, however, it's used between old friends, very close friends, family members, or when someone calls his girlfriend. Depending on the friend, it can't be used and women don't use it in general. So you shouldn't use it.
I hope this was helpful.