yes, for one make sure that the interviewer doesnt lead the interview all the time,
dont forget... an interview is two sided, a number of times ive been offered the position but turned it down because they didnt pass my interview!
find out a bit about the company, size , history , competitors etc and throw a question or two back relating to these,
also only take an interview if you know pretty well what the package is likely to be, otherwise you could be wasting your time,
on that basis never ask in the interview about salary and particularly holidays, you dont want the interviewer to think this is your main concern,
finally at the end of the interview and you want the job,...
ask for it!!!
'i really want this job and believe i can do an excellent job for you, when would you like me to start?'
good luck!