My three tips:
Have a place for everything- could be a pocket in a rucksack, or a little bag (I have one of those zip up washbags), and keep stuff there, but, most importantly, put it back as soon as you've used it. Nothing worse than putting something down like a fire steel down or a tin opener, or even ear plugs, absent mindedly, and not being able to find them again.
If it's really cold, use an emergency bag inside your sleeping bag (don't wear anything else). Will trap your body heat like nothing else.
fire lighting (could be an obvious one here) - dry your tinder against your body. Tinder fresh from the wild can be damp even if it doesn't feel it. If you're not sweaty, I find the armpit is excellent for drying and warming tinder. Really makes a difference.
