You want to arrive to an interview AT LEAST 15mins early. Revise your interview answers so you feel CONFIDENT.
RESEARCH THE COMPANY Make sure you have visited the website KNOW what the company is about and UNDERSTAND what part you would play if you'd be successful.
READ THE JOB DESCRIPTION it's there to help you, KEYWORDS are important because you can sell them why your EXACTLY what they were asking for in their job description (using your own words)
Remember GIVE EXAMPLES; Use STAR as a guide; SITUATION - what happened? TASK - what was the challenge? ACTION - what did you do? RESULT - what was the outcome?
On the note pad bullet point facts of the company so you can refer to them when asked but make sure you memorise them so you only glance down - they will notice your research and be impressed!
Prepare a QUESTION - when would they want someone to start? or when will they make a final decision? you could also ask what needs to be achieved in the first 3months and who will I be working with?
FINALLY end the interview positively - tell them you enjoyed meeting them and if you were fortunate to get the job you would be delighted to work for the company!