Do not go off topic. Keep your thoughts on the things you are good at.
Make a Google Alert on the firm to know latest developments.
Do not be worried to declare you don't know an answer.
Make first impressions count and offer warm greetings with all you speak to.
Advice for those looking for employment:
"Prepare jobseeking arsenal and develop job hunting skills. As soon as your job goals have been targeted, CVs and cover letters can be crafted to display your talents so they match the needs of potential companies."