When an interviewer asks this open-ended question, you have to structure your answer carefully. Although it seems quite simple enough and you may be inclined to give out just any information about yourself that you can think of, such as your favorite dish, music, and color, it really is not as simple as you think. If you want to impress the interviewer with your answer, you need to know exactly what to say when asked this rather tricky question.
You probably do not realize it but the question, "Tell me three things about you, which are not found in your resume" is a question that an interviewer would ask to really get to know you. Of course, it is important that their impression of you would be something that would help them decide that you are suitable for the job. This being said, you should focus your answer on the good qualities that you have; qualities that would prove to be valuable to the job position you are applying for.
As an example, if you are applying for the job of an assistant manager in a department store and you happen to be the kind of person who likes to work with people and possess good people skills then you should mention that in your answer. Make sure to support your answer with examples too because this will prove that you are telling the truth and that you know what you are talking about.
It goes without saying that if you are not clear in your answers, the interviewer might not be able to understand what you are trying to say. Or worse, you would be completely misunderstood and instead of making a positive impression, your answers could impact you negatively. When giving answers, especially for the above question, use words that are simple and easy to understand. You are not trying to impress anyone with your flair for words so do not even attempt to go in that direction. And since the question requires "three things" about you, then stick to it only. You can use ordinal numbers when enumerating your answers so that you will be easier to follow. Start with "first" and then proceed to "next" and followed by "lastly."
Nothing can bore an interview more than a very lengthy answer. This person would prefer listening to brief answers rather than to hear you talk about yourself for a long period of time, so make sure to keep your answer short. A 2-minute answer is sufficient and should be able to give your interviewer a good idea of whether or not you are the perfect candidate for the job, based on the qualities you possess.
One tip to help you achieve this goal is to practice answering this question at home. Time yourself so that you would know if you could stick with 2 minutes and be conscious about not over-explaining or giving out unnecessary information to the interviewer.