You should always prepare for your interview. You can look online to see what questions that are typically asked at interviews for that type of job. Do this and prepare answering these questions. This can help you to know what to expect for the interview so that you can appear calmer. With less anxiety, you will be less likely to make mistakes during your interview and you can give a better first impression. It can be helpful to practice in front of the mirror so that you can watch your body language as well. You should also take a great deal of care in getting ready for your interview. Be sure that you choose an appropriate outfit (no jeans, sneakers, or hats) and are properly groomed before your interview. First impressions are crucial for your interview and your appearance and how you present yourself at your interview can determine how well the interview goes.
You must never be late for your job interview. This could give not only the impression that you are not serious about the job, but it can also give them the impression that you are always late. Employers want employees that they can count on to show up on time. It is also important to never be too early either, as this can also be viewed negatively. Arriving between 10 and 15 minutes early is the perfect time to show up as this shows that you are interested in the job and value the time of the interviewer. This will also help you to relax before your interview and calm any nerves that you may have about it.
Most importantly, remember to be yourself. Employers can tell if you are not being authentic during the interview, which will cause them to think about hiring someone else instead of you. They want to know who they will be working with on a daily basis. They want to know if you are actually a good fit for their company, such as someone who will work well with the other employees.
Interviews can be scary but by following the advice laid out here, you will go in and crush your interview. Sometimes it takes a bit of practice to build up your confidence. After a few interviews, you will have the process down. You may get lucky and get your first job after your first interview, but it may take a few tries to get a job, so be patient.