Hmmm... I also have low self confidence. Tomorrow night's games, I'll try shouting like Marin and showboating like Kevin, and I'll see what happens...
I believe visor was being sarcasticTry it bro, it's useful especially in an "intense match", it will boost your psychology, awareness and fighting spirit......welcome to sport science my friend.

And it's not true that you need to be outwardly expressive to boost any of your abilities.
You can be as cool as ice and win against the very best out there - Yang Yang, Morten Frost, Hendra Setiawan are examples.
And perhaps the greatest example that comes to mind is Kim Dong-moon.