How can you make your students be attention with you for the first houre of your class, can you give a technique?

In the first class teacher  & students are new to each other  By asking few questions and answering them implement the ideas that students have come to gain the knowledge.Indirectly explain how much they are  going to loose in terms of time and money .

Ha, that's a hard one. I suggest strong planning and keep the class interactive as possible.  In addition be sure to followup with a check of understanding, even a simple worksheet or quiz on the days topic.Classes should not be more than 40 minutes...but in UAE many seem to be longer.  The first 10-12 min have a fun activity that covertly introduces the topic for the day.  Once you are doing the lesson, use lots of white board work with student participation. Stick to your plan and have something to do for those who finish first so they don't get disruptive if they are done early.

Best of luck

Charles