There's no fixed or established list- different people follow different sequences. When you say the first grammar lesson, do you mean their first lesson? I'd teach them some basic stuff before launching into a grammar lesson. Start with greetings and identification of self and others, or something like that. Will they be using the language directly outside the classroom? If so, then teach them things like how to catch someone's attention so they can get help in the street, like 'excuse me'.