Smile, and when the interviewer reaches out to shake your hand give him or her a firm handshake. Maintain eye contact with the interviewer while he or she is talking. Be conscious of your body language. Try and sit up straight and keep your hands on your lap or on the table in front of you. You can "break the ice" by commenting on the weather or remarking on a photograph that you see in the interviewers office but it is even better if you can break the ice by mentioning something that you have learned about the company.
Don't Wear Perfume and Don't Smoke Beforehand
If you smoke, drink coffee, or have had something garlicky for lunch, make sure you have some breath mints or gum with you. Try not to smoke before the interview but if you must, make sure that you are not in an enclosed place, otherwise the smell will stick to your clothes. Aside from perfume or cologne, many people are offended by the smell of smoke. If you decide to pop a piece of gum in your mouth before the interview, make sure that you remember to throw it out before you go into the building to meet your interviewer.
Make Sure That You Are Dressed Appropriately
You should be dressed according to the company's policy however, even if the company has a casual dress policy, make sure that you are at least wearing smart casual clothes. Most Call Center Companies are not really strict with how you dress up but it is always a plus to look smart and presentable, you may Click this link for some tips on how you should look. Check your appearance in a full length mirror before you head off to the interview to make sure that you haven't got any hanging threads or lint that should be removed. Make sure you shoes are polished and go with what you are wearing. If you are wearing a suit, you should be wearing business shoes, not black or worse, white sneakers.