I think this topic has been covered on DD, but maybe not recently.
http://www.netjobs.co.uk/tips-interviews.htm, or do a search on the net for interview tips.
In addition, my tips would be:
The company:
Research the company and have a look-see at least at their latest annual report;
Be prepared for those "usual" questions and boring typing tests;
Always try to turn a negative into a positive
Remember that you are at the interview at THEIR invitation, so they must see something good in your CV;
Ask questions about the company, its plans for expansion etc etc;
Ask questions about terms and conditions of service;
Compile a list of questions and take your notebook into the interview. This is not a memory test, so they shouldn't mind if you say "I jotted down a few questions, and I would just like to refer to them". If there are two directors that this post supports, then you need to clarify how the workload will be divided, who is the line manager, what are the priorities, what input you will have into the company etc etc
Presentation:
Be in good time for interview;
Dress properly (a good suit and shirt, or dress and jacket - no spots and stains and no droopy hems) and, if you are at work today, freshen up before you go out for interview;
Take a copy of your CV and certificates for educational milestones (degree, business college diploma etc);
Body language is important: stand and sit up straight, look people in the eye, smile when it's appropriate
