When you are diving, don't stick yourself into their mouth. Don't touch them. Don't feed them or bait them. The rest is just up to chance. Shark attacks are super rare despite people actively seeking them out for photos and cool experiences. This is because they have zero interest in humans other than to avoid them.

This is kind of like a fear of quicksand. Movies made it out to be a huge problem. Shark repellent and sharks with laser beams on their heads taught us to be afraid of them. Personally I'm more afraid of jellyfish. I hate those things.