If you have been lucky enough to be offered a job interview, then you will want to make a really good impression. In order to do this, then the most important thing to remember is to smile and be friendly.
Your qualifications and your experiences on your CV will have impressed the employer enough to offer you an interview, so this part of the process is about making them like you as a person. After all, they are going to have to work with you on a daily basis, so it’s important for you to get across that you will be a happy, keen person to work with.