Be prepared to answer the standard questions: What are your achievements in your current or a previous job. What are the failures and how did you recover from them.
When asked for the reason you are looking for a new job, the safest answer is that your are looking for another exiting opportunity.
Have a salary in mind to ask for so don't sound ignorant of salaries in your industry.
Limit your answers to what is asked, or else you will get questioned about something else from your answer for which you are not prepared!
Never arrive late for an interview. Arrive Early! It shows you are taking this interview seriously.
If you are interviewing for a job that involves a change of career, you may not be able to link experiences from your previous job to the new job. In that case try to link them at an abstract level. For example let's say there was a tough deadline to meet in a previous job. You did not buckle under pressure and handled it well. That behavior, that you did not buckle under pressure, could be applicable in the new job.
Know you CV well. If the interviewer asks you about a particular project or a company you worked with a long time ago, do not say "Oh I don't remember that one well". So before you go for the interview, read your resume and try to recall all you may remember about every project and company.