First thing is check your spare tire pressure. Check fluids. Do a visual check under the hood and under the truck for stuff obviously hanging off like it should not be.

Secondly, think through weather situations and have clothes to meet all conditions. Be ready to get soaked and it not kill you from the cold.

Thirdly, stash some snacks and water to get you through 48 hrs of being stranded. Add in some baby wipes for your butt and for cleaning off a little.

Tools obviously. Nothing crazy, but a wrench set is common sense. As another stated, traction boards if you intend to do real off reading.

The rest, to me, is personal preference.