All companies perform the interview process in different ways. Some companies like for you to come once and interview with all the necessary people and other companies like to have several rounds of interviews before hiring.
One of the hardest types of interviews to survive and actually make a good impression in is the interview that lasts for four hours or so. When a company decides to let you interview with all interested parties all in one day, it sometimes turns into a marathon session lasting four hours or more. Here's how you survive the marathon interview.
The first step you should take to survive a long interview is to practice answering some of the tougher questions. Generally, if you are interviewing with four or more people, you will hear the same questions several times. So, be proactive and have answers for questions like: Why did you leave your last job? What are your weaknesses? And why do you want to work for us?
Memorize pertinent facts from your resume
While everyone generally knows what's on his or her resume, it is very easy to forget certain portions when being interviewed by many different people during a single interview. So, take the time to peruse your resume carefully and know the content very well.
The day before the interview, make sure you do not eat anything that might upset your stomach or send you to the bathroom. On the day of your interview, don't drink too many fluids before your interview but hydrate yourself enough so that you will not have drink cravings.
Bring some small mints like Altoids or Tic Tacs and keep them easily accessible in your pocket. I usually keep them where I can reach them even if I am in the middle of talking to someone. That way, if I get a scratchy throat or parched mouth, I can just pop one in and keep on with the interview.
All in all, surviving long interviews is just a matter of planning ahead and taking some necessary precautions in the foods you eat and how much you drink before your interview. It also involves being intimately familiar with your resume and having some answered prepared for those difficult questions.
Finally, it means that you should be rested before your interview, you should show attention and intelligence during your interview, and you should knock the socks off all the people you meet!