so: i decided to put a new idea abot Minecraft and i discovered in PE version but you can do it in the complete version too.
Step 1: What Do You Need?
you need cobblestone walls and obviously water. The cobblestone walls are gonna be our respirator.
Step 2: How Can You Realize It?
you have to use the cobblestone walls in this way: the cobblestone wall putted in the water will make a little space without water. Standing in that space you're gonna be able to breave.
Step 3: Thanks!
see you next time with another idea!