what do you like to say at the start of a match?

I'd say.....
You have the right to remain silent.
Anything you say can be used against you in the court of law.
You have the right to have a lawyer present during questioning.
If you cannot afford a lawyer, one will be appointed to you if you wish.
You can decide at any time to excercise these rights and not to answer any questions or make any statements....

"I used to be quite violent when losing a match, but I tend to be OK now, and there shouldn't be anything for you to worry about..."

a loss in chess should provoke a reaction , getting it looked over and taking on board where you got beat and how , or you could do an old ziggy and inspire loads of draw offers when you are in a poorer position lol ,

Absolutely, someone (inkiapetteitor) understands at last that chess is not dice, one does not have to throw a six to start.
It is not a game of luck it is a game of skill. To wish someone luck at the start is misplaced and rather trite pseudo political correctness. Get real, guys, chess is a killer game and wishing someone luck at the start is naff. Naff. Can anybody imagine that Fisher wished Spassky luck at the start of their World Championship match?
pseudo political correctness. Get real, guys or stick to luck based board games.