But a worse mistake is to go on and on, and make the interviewer wonder if you will ever shut up so the next question can be asked. Practice with a friend so that you learn to feel how long 30 seconds is. Answers longer than 30 sec. Save your one or two long answers for questions that give you a crucial chance to show yourself at your best. If possible, learn about the professional interests and accomplishments of specific people involved.
Dress codes are in transition.
Several years ago, the invariable rule was that men must wear a suit and tie to an interview and that women must dress with comparable formality. In the recent job market when positions have been difficult to fill, some organizations have adopted much more relaxed dress codes in their internal offices, and it is more difficult to know how much more formally job seekers are expected to dress than they would on the job, if hired. It is not yet clear whether this trend will survive if future job markets are less favorable to job seekers. You might start by asking what the dress code of the office is, then dress somewhat more formally for an interview. It is important to know which kind of interview to prepare for.