For glassing in the cold and dealing with breath, you pretty much just have to learn a conscious habit of blowing down and away on the exhale. You can't just let the warm breath float around your face. Blow it out and down, away from you.
Blowing down and away from your face is kinda hard to do when wearing a balaclava.
Our winter prone league matches generally start in March. I wear a balaclava to keep the windchill off of my face. Warm air leaks out around my nose and up into my shooting glasses causing them to fog up. I tried the dawn trick and it worked like a charm. I can take my glasses off, they'll cool off and not fog up when I put them back on once they're treated.
