I am talking about right body language, behaviour during the match watch this there are many players they say something to themself so lets say shuttle is coming I hit, I made a shot to the net and this person say to every body you stupid and he is saying to him, he is stupid because he made mistake and then when he made another mistake this time he shake head like this tell every body I am not playing well but I wonder why he is doing it when I made mistake I knew why I made mistake so I can change it next time, my focus should be how can I change not to make mistake next time rather than focus on why I made mistake, angry and show every body, especially showing his opponent how I am disappointed and this behaviour only give my opponent confidence you should play like deep lake when the lake is really deep it does not show no body knows how deep that is, you should play like that do not play a match like shallow stream so little happens you behave something, every body knows what stage you are in emotionally ok, once you do that you are not dangerous player to your opponent because your opponent can see, what you are how deep, how small you are so do not show your disappointment but you can show, how tough you are, how serious you are rather than telling every body how much you are playing badly