1. Wear The Right Kind Of Clothes
Wear appropriate baselayers, such as merino wool or insulating synthetics, with an insulating layer on top.
Wear socks and a hat (you lose a lot of body temperature through your head, so don’t forget this one important item)
Pack a pair of thick woollen socks specifically for sleeping in and make sure you keep them dry.
2. Think Fire
When you arrive at your campsite, start your fire before doing any other setup.
3. Choose The Right Campsite
Take note of where the sun will first appear at sunrise.
Angle your tent to take advantage of the early rays while shielding the door from the wind.
4. Go To Bed Warm
Warmth originates from within, and any insulation from a sleeping bag or clothing is merely concerned with keeping it there.
Get warm by doing star-jumps before going to bed or performing sit-ups or press-ups in your sleeping bag.
5. Eat Late
Eat a hot meal immediately before sleeping, and make the meal a fatty one.
Avoid too much liquid before bedtime, as it is painful having to get up in the middle of the night for a wee.
6. Add More Layers Outside
Get one of those thin metallic survival blankets and drape it over the torso area of your sleeping bag.
7. Keep Your Sleeping Gear Dry
Protect down sleeping bags in particular from getting wet at all costs.
Avoid breathing into the sleeping bag while sleeping, as it introduces moisture and down doesn’t work when it’s damp.
Squash all the air out of your bag as soon as you get up in order to expel body moisture, and dry out your bag fastidiously on a daily basis whenever you get the chance.