Your CV
Your CV is a document that YOU wrote and you should know it back to front and inside out. Make sure you know dates and time scales as well as any details you have supplied about previous roles. You need to be able to answer questions promptly and confidently.
Interview Format
Find out what format the interview will take i.e. CV based or competency based. Will there be a requirement for a presentation? Will you be required to undertake tests/assessments whilst at interview? You should be advised of all of the above but if in doubt ASK!
Body Language/Speech
Be aware of nervous traits. Consider your posture, ensure you sit still and sit up straight. Maintain good eye contact throughout.
Be measured in your speech, take time to think about what you want to say and ensure your answers are clear and concise.
Prepare Answers
Before your interview think about some questions you may be asked so you can be prepared. If it is a competency based interview go through the job description thoroughly and think about relevant scenarios in your career which demonstrate the skills required for the role. You will need to have a specific scenario for each question asked.