Prepare well
You must prepare a list of probable questions to prepare them well. The interview panel mostly picks the questions from candidate's background. The questions are mainly either technical which will be related to your educational/work experience background or they will be personal questions which will be related to your life, family, city, future plans, etc. Concentrate on both the fronts. To give you an idea, some of the questions that are often asked in the interview are - Introduce yourself, Tell your future goals, Why you want to join us?, etc.
Stay Confident
Be confident even when you don't know a certain answer. Confidence is a strong way to impress the interview panel. Leave all the stress back home and enter the interview room with positive attitude.
Dress well
You must look neat and clean. The clothes should be ironed and clean. Polish your shoes and wear a tie. Groom yourself well before appearing for an interview.
Sound positive
Talk about your achievements. When they ask you to introduce yourself, you have a great opportunity to talk about your past achievements. After talking about your educational background and family, do include your achievements.
Take your time
Don't be in hurry to speak as you hear the question. Take few seconds to frame your answers well and then speak. Some people end up speaking irrelevant in hurry.
Physical gestures
Look into the eyes of the interviewer. Do make sure you maintain an eye contact while answering. Looking downwards or elsewhere is never appreciated. Do not shake your hands or legs and keep up the smile.
