Once again, torches have come to the rescue. Whenever you go on a trip underwater, be sure to take a bunch of torches with you. They can help you breathe underwater for a longer period of time. By placing a torch on a block, it creates an air bubble for a short time. You have to place it on a vertical surface that’s right next to your head for this to work, but it’s enough to ensure that you can get some extra breath in an emergency.
This hack works with any item that comes with air around it according to the game, which includes not only torches but also easy-to-make items like ladders, signs, fences, and doors!