If you are a newly-graduated teacher, it's quite possible that you are being interviewed to teach students only a few years younger than you and you need to be able to assure your prospective employers that there is a clear distinction between you and your students. In terms of behaviour this means acting maturely. In terms of your dress at an interview it means deliberately dressing to emphasise maturity.
Listen and think before you speak
During a job interview, listening is just as important as answering questions. If you're not paying attention, you're unlikely to be able to give a good response. Listen carefully to what your interviewer says, pay close attention to their questions and think before you reply. It's very tempting to try to appear confident by responding immediately, or to cover your nerves by talking too much, but all too often this will be when you make mistakes. If this is your habit, force yourself to stop and consider a question for a few seconds before replying. If you're not totally sure about a question, never be afraid to ask for clarification. If you are asked to answer a hypothetical question, for example about how you would react in a given situation, be sure you have all the information you need before you reply. For example, if you're asked what you would do if a student told you to f*** off during a lesson, you might ask if there is anything else you need to know about the child...
Plan your responses to interview questions
This is simple common sense. Even an inexperienced teacher will be able to predict a good percentage of the questions he or she will be asked during an interview. Answer those questions. Write the questions and answers out. Then read your answers and ask yourself another question: is this what the recruiter wants to hear? Refine your answers, practice them. Most applicants get nervous during interviews and having ready-prepared questions can help relax the nerves a little.
Interview tips are available from countless sources. These can include advice on body language, questions to ask employers, answering tricky or trick questions. Learning a little about these aspects of interviews won't guarantee you get a job, but it is very unlikely to hurt your chances. If you're serious about wanting a career in teaching, be serious about how you approach interviews.
Finally, if you are newly-graduated, don't be surprised if you get offered a substitute or assistant teaching position instead of the full-time job you hoped for. Treat the offer as an open door and accept it. Many schools recruit new teachers in this way, allowing them to check that the teacher fits in and can adapt to their policies and students. They rightly want to be sure that the person they employ will fit their needs.
Teachers of English as a second/foreign language tend to face slightly different challenges to teachers in 'normal' schools. See our related article on finding work as an ESL teacher.