Here is a very inspirational 30 second Youtube video by Rafael Nadal (link to Youtube) (a Masterclass in pre-match communication)
1). What do you notice about Nadal vs. Casper Ruud's non-verbal conversation?
2). Which player does your own body language remind you of? Can you change your body language and mentally prepare before you play any match?
3). Why is this important at all? How does this affect "real life" outcomes?