Hi dear friends

if they �re children or teenagers, establish a few rules (speak english, no chatting, no mobile phones... depending on the context) right from the start, show them that they are here to work, talk about the things they will need (book, notebook, pens...) to make sure they all know what they �re supposed to bring to every class.

If they �re in high school, try to make them write the rules they have to follow, it works better when they establish the rules rather than being told not to "...". You can write 5 sentences on the board that talk about you (eg. I lived in England - I �m 50 years old - I �m spanish...) and they have to say if they think it �s the truth or a lie - don �t forget to tell them the truth afterwards. Then ask them to present themselves in the same way, the benefit of this activity is that they have to present themselves and they learn more about their classmates when they try to guess if they �re lying or telling the truth. (see a powerpoint of mine that I uploaded a couple of days ago to give you ideas)

The first day try to be very strict with your students, don`t let them do whatever they want.

I fully agree to all of the advice that has already been given to you. You are not to try to make friends with your students, try to be strict, but just, understanding, but not too much. One more idea, when i first saw my students, I told them not to be afraid of doing a mistake, more over I strongly advised them to do mistakes, because that is the right way to learn something.