Start by finding out! Start with a short conversation in which you ask her to tell you about herself and why she needs to learn English. If she can't cope with this, then she's a beginner - if you can find out the info you need (see below) in her own language. But then have some materials at beginner level to turn to for the rest of the lesson - a lesson on introductions, would be fine and is included in most beginner coursebooks. If she can cope with the conversation however, you can base the whole lesson on a) the general "getting to know you" conversation about her b) a structured Needs Analysis questionnaire c) a level test. Just Google
level test EFL and
Needs Analysis EFL to see examples.
But eg in the needs analysis you'll be trying to find out things like :
Personal info : Who is she? Past life including studies, work etc; if she doesn't work, how does she spend her day? interests and hobbies?
Experience of learning English : when? where? exams taken? stays in the US/UK or other English speaking countries?
Experience of using English : when does she usually use English - for travel? to socialise with company clients/colleagues? to read/watch films? for her own work?
Why does she want to improve her English now? - the same as above, or something specific in the future - eg she and her husband will be moving to the US
What has she enjoyed/disliked about learning English in the past? eg does she like learning through conversation? through systematic grammar study? does she luike things explained in her own language or everything in English?
What has she found easy/ difficult about learning English in the past: eg listening? grammar? speaking?
What are her priorities for the course? eg improving her ability to have social conversations; improving her ability to attend conferences for her own work etc etc
You really need this info to design a decent course - so if you can't get it in English and can't speak her language, I'd anyway have a translated version of the questionnaire and ask her to fill that in - then get someone to translate her answers for me.
The info you get will then help you choose the materials for the course. Eg if you find out she needs to learn because she has to host/attend dinner parties with her husband's colleagues/clients, or maybe show their accompanying partners around the town, you know you need to focus on general social conversation, but also things like talking about food, explaining the history/sights of her town etc. If on the other hand it turns out that she works as a doctor and needs to attend medical conferences in English, you'll be looking for material on that.
In the lesson, follow the Needs Analysis up with a test to find out what level she is - and that should take up anything up to an hour and a half (you don't say how long the lesson is).
If there's time left over, do a bit of general conversation - eg tell me about your life when you were a small child. Where did you live? did you have lots of brothers and sisters? what's your earliest memory? do you remember your first day at school? etc etc While she speaks, take notes of her mistakes - which will give you more info about her level and needs. Spend the last fifteen mins or so focusing on a few of those mistakes which you think you can explain quickly and easily.
Alternatively/additionally, ask her to think of five questions to ask you about yourself, and answer them fully (you've asked her everything, now it's her turn). This helps establish rapport and shows you her listening ability and ability to form questions.
Filling up the first lesson is rarely a problem - it's what comes next that's the real challenge
