Baph

Do your research!!! Research the company, what it does (outside of the job role you're applying for), who it's clients/suppliers are, what they do. If you can find out who MIGHT be interviewing you, read up as much as you can on them.

Learn everything you read, and memorise it. Once you've got that down, remember not to repeat parrot fashion in the interview, and you'll be fine.

Show them you know what the company is about, and you'll come across as keen to work there, and a self motivated person. Assuming you have the qualifications that are NEEDED for the job, and you fit in with the team they already have, research will mean the difference between "When can you start?" or "We've got a few more people to interview, so we'll be in touch."