Cold weather photography tips?

Novice photographer here - got myself a Pentax camera (K5 ii s if it matters at all) and a few lenses this last spring, and have been learning a ton and having a blast. Even took a few decent photos along the way. Looking forward to some great winter shots, but am wondering about strategies to keep the camera and lenses functional in cold temps. (Think mountains in NH - not the Arctic, but can get pretty chilly.) Obviously I can put batteries in a pocket/sleeping bag to keep them warm, but what about the camera body and lenses? Things I should watch out for or precautions I should take? Appreciate any advice you might have!

Here you go!!! your main battle is preventing condensation .... xD

https://www.youtube.com/watch?v=cjov6toYh2I

Shot with a k5iis for years. Never had issues with battery drainage at cold temps even at -10F. I did always take them out to sleep with them at night. I usually kept the body and lens in my tent but otherwise didn’t do anything special. 

Much appreciated!