Get to know your students. Each class is made up of individuals with varying preferences, and in some cases with varying levels of English. They may be from different countries and view the world differently. Find out what their immediate goals are for using English and what their future goals are for using the language. Perhaps they want to confidently read emails from their child's teacher, or maybe they want to enter college at an English-speaking university.
Prepare your lesson plans well in advance. A week's worth of lesson plans ready before your first day can will reduce your preparation time and anxiety before each class. You will also have more time to prepare materials for each lesson, such as bringing in realia (real objects used to help students learn vocabulary) or copying worksheets for them before class starts.
Incorporate physical activities into each lesson. This might include students playing a game, walking around the class with a partner talking about classroom objects, or role playing in which students stand up and move around the class. You can also have students touch realia during the class or use it during role playing to help them remember the vocabulary from the lesson.
Avoid using slang or speaking too quickly in class. New teachers often make the mistake of using colloquial language that is unfamiliar to students. It is also important to have students learn as much of the language or forms of grammar as possible without lecturing them. Ask students what patterns they notice or what words they know related to a particular topic. This will get them thinking about the lesson and coming up with some of the lesson's main points themselves through observation of patterns and connecting with related ideas.