When first asked something, dont say the first thing that comes into your mnind. Give yourself time to consider a better answer
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You might look stupid in the moment, but it doesnt matter. The answer will be much better.
Try and get questions for any interview in advance.
Our first answer is usually outdated - either its an answer we came up with a long time ago and havent reviewed in light of recent information, or its an emotional response.
Wait a few days before making a decision, or acting on a decision.