Honesty and Courtesy
Be sincere and avoid using cliché and looking too humble.
Request the interviewer to repeat the questions if you do not understand well.
Do not overstate your merits and be honest. Depending on the job requirements, focus on your relevant strengths.
When you do not know how to answer a question, tell the truth. You will be more embarrassed if the interviewer finds out that you are boasting.
Answer Systematically
The use of jargon/ technical terms may reflect your knowledge or interest in the industry. However, over-use or misuse of jargons may make you look pretentious.
Do not simply say “Yes” or “No” when answering questions. You will look passive and unreliable.
State clearly your points with elaborations and concrete examples. Your arguments will be more persuasive.
Intonation
Use firm and positive tone.
Avoid speaking in a mix of different languages.
Avoid using excessive tentative words. Otherwise, your answers will be unduly long. You will also look unconfident and flippant.
Remedy for Wrong Answer/ Response
Under stressful situations like a job interview, wrong answers may be unavoidable.
If it is a serious mistake, you have to apologize and state what you really mean.
Do not give up even if you have made some mistakes. Concentrate yourself on the questions to come.
Others
Do not interrupt the interviewer. This is extremely rude.
Do not appear impatient or surprised when the interviewer raises some questions which are totally irrelevant to the post applied. The interviewer may just wish to test your common sense and analytical power.
Do not panic when the interviewer disagrees with your viewpoint. Some interviewers may do this intentionally so as to observe your response.