Here's another one to try. Extreme though. Only if you are really fit. Go to the beach or a pool, jump in, go under, the deeper the better, hold your breath. When you think you are gonna drown, get someone to hold you under a little bit longer. Trust me, I've surfed for around forty years, it takes a lot to drown. When you are kicking for your life, come up. You won't need a nose. You'll realise why snorkels go in your mouth.
PS spit out the gum early, or you'll die.
