I was 30 feet underwater, kneeling on the sandy sea floor of Nari Nari, when my scuba instructor Brian told me to flood my mask—a skill every budding diver needs to complete before getting certified.

Aside from the actual swimming, every scuba skill I practised in the ocean filled me with dread. Aren’t hobbies supposed to be fun? Read more summer essentials Would you rather go to space or the ...