The only way to learn to respond positively to competitive pressure is to experience it in practice, over and over again. Don't wait until competition to experience pressure. Decide as a team to practice with the same focus, urgency, and accountability you'll need on the day of the competition.
During:
Treat every drill like it matters (because it does). Communicate, execute, and compete with game-like intensity so pressure becomes familiar rather than intimidating.
After:
Did today's MindRep help you? How did today's MindRep help you? Do you want to own it and make it a consistent part of your training?