How do I subconsciously train someone to stop sneezing very loudly without them knowing it?

I wouldn’t “confront” them. Just tell them.

Sneeze louder and more obnoxiously. This obnoxious sneezer will look at you and think, “is that what I look/sound like?” Thus, they will be more aware of their sneeze. ;-)

The trouble with subtlety is that it can be missed easily. You’re better off with some variant on, “Dude, you sneeze like a jet engine!,” or perhaps, “Would you please stop scaring the wildlife?”
Humor, in the case of presenting an uncomfortable idea, is indispensable. As the song says, “just a spoonful of sugar helps the medicine go down.”

They can’t help it. It’s not like their trying to sneeze loud, that’s just the way they sneeze. I know this cause my dad sneezes very loudly, and he can’t help it, niether can I. What gave you the idea that someone could sneeze less “obnoxiously”, that it would even be possible? Have you ever noticed how mexicans sneeze, I love it, it’s the greatest sound.

Oh gracious I know someone just like this! He literally screeches the “choo” and it makes me jump! You also can’t even vaguely suggest anything to him or he will do the exact opposite of what you ask, He has to prove that people can’t boss him around. I ask him to slow down a little and he floors it. It is consistent lifelong behavior for him. He’s so twisted I am not even sure what would be a positive reinforcement for him. I guess tell him to do the opposite of what you want him to do. “Scream louder when you sneeze! It’s awesome!”

This is just a random note. I think the guy I am talking about shows a LOT of signs of Tourette Syndrome. I don’t mean the silly kind comedians use as an excuse to curse. He has facial winces and makes other strange noises at times.

Go to magic school. They teach that stuff.

Ok, use hard core mind control. Get a box of Kleenex and put some funky stickers on the box, something embarassing. And next time they sneeze, bust out with the box and make a show of handing it to them. Be nice. Or just fake sneeze the best you can every time they do. Or bust out a digital recorder and ask them if you can record their sneeze, tell them that it’s for an art project, something sociological. Or just say “shut up” as nicely as you can.

It can be maddening, but I’m not sure you can re-train someone to sneeze differently, since sneezing is involuntary expulsion of air. Funny thing, though, as a kid, I was always horribly embarrassed by how loudly by dad sneezed in public places. Sounded like a canon going off. But now, 30 years after his passing, I’d give a million bucks to hear it again.

Gosh, I’m embarrassed now. I’m a really loud sneezer. I’ve tried to dial the volume back on the ol’ “sneezaphone” with no luck. Sometimes I jump up and leave the room if I feel a one coming on, but I’d have to leave the state for no one to notice. I’m sure I’ve embarassed Katawagrey a time or two….