If I have an interview for a customer service agent position, how can I keep my positive body language during interview for as long as possible?

To keep your positive body language during interview for as long as possible, you should follow these steps:

Seat straight

According some countries postures, men should avoid cross the leg showing the plant of the shoes

Avoid too many hands/arm gesticulations (will confuse the interviewer and distract)

Show interest for what the interviewer is saying, doing an "active listen" (means that is understanding what´s being told)

Show confidence looking eyes to eyes

Adopt an motivated attitude, making questions

Try not to talk too fast

The first thing is to be honest with yourself, as if not you will deliver a wrong body language that could cost you the job. Then, you should remain calm and smiling as you're applying for customer service position. Finally try to overcome the stress in order to answer the questions in the best way.

Be myself, be professional, be confident pay attention and involve myself as much as possible

As i heard, Body language and personality expression in an interview are vital.  Employers hire the candidate who has the personality and a '' team fit'' . Here are the tips which would help you out during interview that makes you in positive moods;

1.  a firm handshake
2. appropriate eye contact
3. a genuine smile
4. appropriate laughter
5. relax

as much as your effort before interview get yourself prepare for video and record your body language for an interview,  do so will help you more easily identify your behavior. Seeing those tendencies for yourself can make it easier to recognize your fault and remedy.

To keep my body language during interview as long as possile i must be:

always alert and pay attention to the interviewer.

look direct into the eye of the interviewer ,eye communication shows that the candidate is confident .

candidate must not have anything that might be obstructive to the interview ,ie ,avoid attending to calls during the interview.

candidate must not be figgitting during the cause of the interview

all communication must not be based on assumptions,you have to answer what you know,a primary objective of holding an interview is to assess your capabilities against information you presented to interviewers.

avoid using sign language or stammering,be confident

Just be confident and keep an eye to eye contact.

As an Interviewer you have to be on top most professional manner, pay attention to details, keeping an eye contact is very important. Limit unnecesary body movements that can cause a wrong signal to the interviewee.

keep an eye to eye contact

Keep on focusing on interview with eye to eye contact

but nonverbal communication ( body language ) is also

mandatory during interview just should not be abusive

by keeping an eye to eye contact, being confident