I need help

Hello! Could anybody help me, please. I'm just a student of a faculty of foreign languages. I'm going to teach English a woman. She is just a beginner. However, I don't know what to start with. Can you tell me what I should teach her first? Should I start with vocab? or may be the verb "to be'?
It's very important for me. I'm really looking forward to hearing a piece of advice...