You know, its kinda funny, but it seems that with a lot of stuff like this I'm already trying to do it, but I don't know why. Recently on my runs I've been trying to keep my breaths smooth and silent, but I wasn't thinking about efficiency, I just thought it was really annoying when the rest of my body was totally silent but I was panting away like a dog. We also focus on using our diaphragms in choir, but for some reason I never thought to apply it to my running. I'll be sure to work on this now that I'm aware that it actually is better and not me just being crazy about making noise. I'm definitely not used to nose breathing, but I bet I can get used to the lower air flow, just like I have to whenever I'm swimming and can't be gasping constantly. Lower volume will probably force me to focus on the rest of these points in order to get by.
Breathing deeply and exhaling completely will probably be my biggest problem, just because I have a lot of lung capacity from running, swimming, singing, etc. and I'm used to barely breathing at all unless I'm running. As long as I remeber that I'm supposed to do it I'll manage though. I'm not quite sure about running with water in my mouth, but heck, its worth a try. I'll probably end up drooling on my self or something though, haha. Good stuff.