Can you give me good advice about how to act and look when going into an interview?

help....Can you give me good advice about how to act and look when going into an interview?
The more relaxed you are , the better chance you have. So dress casual and try to think of the interviewer as a friend you have not seen in years....you are going to tell her all about your life over the last few years.Can you give me good advice about how to act and look when going into an interview?
Be sure to smile alot and don't be fake because if you get the job then you'll have to deal with your lying or being fake in the interview. Always ahead of time check to see what's the appropriate way to dress for the job you're applying for and dress at or above that. Prepare for the questions that they'll most likely ask ahead of time! Preparation goes a long way and they'll notice and appreciate that as well.
Yo should probably show a bit of your personality, have great manners and dress casual or formal, dependong on the job.