to make a judge LIKE YOU
Act like you're there to perform, since you really are.
All your gym training, warming up, and pool lessons are irrelevant to an athletes ability to perform well. The performance is 100% mental, as most of the athletes you are competing against, also have been training, and are in shape. So it comes down to a few items to consider, that will give you a bit of an edge, and, hopefully, put you on a path to compete in an elevated way.
You don't NEED to be an natural performer, you only need to act like one.
Confidence, Stand-Tall, Dare folks to look at you. Manage yourself first, and focus on task at hand. Think about succeeding and avoid thinking about fears and things that can go wrong. Leave the bags of crazy at home, as too heavy for the competition. Look like you have prepared to win. Your friends, your coaches, your adversaries, your parents are all to be put aside, as you focus on completing each dive. No do-overs.