First of all you have to make sure to get to know your english students, their weaknesses and strenghts and if possible, to remember their names.I like to know about them,their hobbies, their expectations...so I can fullfill them all.
Once this is done, it's essential to establish the goals of the course, the way of evaluation as well as homework and necessary things to remember so everything's clear since the beginning.
We cannot forget about establishing rules that will help us to keep classroom management as possible.If they are involved, it will be easier and better cause they will feel part and important in the teaching process.
MOTIVATION is a MUST. If they feel comfortable and understood, everything will go fluent and there won't be no need to repeat things again.You are not their friend but an english teacher is a role model so you can have a good relationship with them and set a good learning environment.
Last but not least, whatever provided feedback is welcomed. You need to know if they liked English or not before taking english lessons, their experience in other countries or using the language, their scores in the school or whatever information you can use in advance.
Finally, there is also time for FUN!!. You can bring worksheets or play games related to the content you need to review. That way, they won't feel oblied to review or being tested. Otherwise, they will prove it themselves through didactic activities!
Now you have your plan for the first day or become a tutor and start planning it. Make sure you do your best!!
