[saopinax]

Adding to what's already been said, you never know who is standing around you or who is in earshot. It's best to treat everyone with courtesy and not say anything disparaging. I've watched things get said that have had a way of coming back to people, either during shinsa or at a banquet. Or worse.

As others have already mentioned, either find a safe spot to warm up quietly or volunteer. When you're busy volunteering you don't have time to worry about your upcoming matches.