Weight, tyres, look for traction sand.... comes in watertight bags, it works as ballast, and u can cut em open and pour out the sand around ur drive tires which MAY help if stuck.
Also, chains, keep the gas tank full, do not use cruise control, you may be better off with an ABS killswitch (ymmv), proper tire pressure, watch those overpass/bridge transitions.
Course roadside assistance may be a good idea as well as a snatch strap