Advice on Interviews

Preparation is all. So make sure you do your research by reading the assignment brief, looking at company websites and, in the case of retail vacancies, making a site visit.
Come to an interview armed with lots of questions, and ensure you use the time set aside for questions to your full advantage.
Maintain eye contact with your interviewer and try to pick up on their body language.
For competency based interviews, identify which behaviours will be key to your success. Have two or three examples ready for each competency which best illustrate your suitability.
Don't worry about using examples which have already appeared on your CV. However, make sure you don't use the same examples for all competencies.
It is far better to draw on events which have occurred in the last 12-18 months. The detail will be much clearer in your mind.