What psychological trick do you use when playing OTB?

On the board I saw many kinds of cheap tricks, singing awful songs loudly or ticking on the table or moving head right and left..
And most of all hiting the pieces strongly which makes a loud and noise sound which distract me..
All that means cheapness and a well chess player should never use thous garbage styles.

Before the round, if I don’t know my opponent very well, I ignore everything and just stare at my opponent. I don’t move, I don’t fidget, I just stare.
I stop when the tournament director tells us to shake hands. I mean, what’s he going to do, call the TD, “hey arbiter, my opponent stared at me and made me uncomfortable and so I lost my game, can I have a rating refund”??