Shelter
Tarp setups that hold against the weather.
A tarp and two knots will keep you drier than a bad tent and weigh a quarter as much. Shelter is the first skill, because cold and wet are the first dangers.
The setups
a-frame classic, sheds rain, needs two trees lean-to one ridge, open front, face the fire plow point one anchor, angled into the wind
The rule
Pitch before you're tired, and read the wind before you pitch. Shelter that faces the storm is no shelter at all.