Be honest and calm
Have up to date relevant documentation for your role.
Show Continuous Professional Development evidence.
Maintain a professional attitude at all times, don't be too intimidated to ask any questions of any topic that is related to the position.
Having a clear and updated CV with the relevant detail helped. I made sure I was a few minutes early - luckily the HR consultant was running early and was able to see me straight away. Having a good understanding about the position that I was applying for also helped.