In a technical interview, learn to recognize when the interviewer is trying to help you, and take notice immediately when they do. If they say, “Do you really need to use a float here?”, nine times out of ten what they really mean is, “Stop trying to use a float here.”
As an interviewer, it’s really unpleasant to be trying to throw a candidate a life preserver and have them keep shooing it away.
(Sometimes “Do you really need” questions are a trap and the interviewer is testing your confidence, but in those cases it’s usually said with a completely different tone.)
My other tip is for the squishy personality test interview: come into it smiling, and keep that up for no reason. The interviewer will usually start doing it too, and that leads their brain to think, “I’m smiling, so I must like this person.”