However, the reality is that during a game you are on your own. Nobody will whisper in your ear when you have reached a position that is, in fact, a tactical puzzle and all you have to do is solve it.
Emmanuel Neiman offers help. He has identified a number of signals that tell you that somewhere in the position you are looking at there is a tactical blow just waiting to be found. What you need is a way to read those signals. What you need, and what Neiman helps you to acquire, is a Chess Tactics Antenna.