Pay attention to where you locate your shelter. A difference of just a few feet can make a difference in exposure to wind, which is likely to be your biggest problem. Brush and thickets will shield you from breezes, while that inviting clearing may be rather drafty.

Avoid the bottom of drainages if you are concerned about the cold. Temps are often 5 to 10 degrees warmer only a few feet upslope.

Evaluate the possibility of traveling during a portion of the night. Exercise keeps you warm. This is dependent upon the terrain, your familiarity with it, the light sources you have with you, and moonrise.

If your fuel is limited, consider not building your fire until later in the evening or early morning. In my experience, 3 AM is the toughest time for an impromptu overnight.

Eat well and carefully. Ingest fats for long term metabolism. Bundle up early and stay out of the wind. Get insulation on your head and neck

Keep your spirits up, maintain a positive attitude, and look forward to a nice cup of tea to get things started in the morning.
_________________________
Geezer in Chief