1/ Treat people how you want to be treated. I use this basic belief, whether I am driving, walking down the road, buying stuff in a store, at work with customers and fellow staff, my friends, my family or strangers. It doesn't make any difference to me who they are or whatever attitude someone approaches me with. Most people are pretty decent, and will lighten up when you treat them with honesty, kindness and respect.
I realize that you may not want to be this fair to a lot of people; like some rude, dumbass jerk or maybe police and other authoritative people. But, they might just be having a bad day, and upon meeting a decent 'you', they might come around. If they don't, just deal with them at arm's length and walk away. It's your call, every situation is different. Tip: Don't argue or be rude with a cop, you're only asking for more trouble than it's worth.
2/ Drive to arrive alive. Slow down, you'll save gas. Pay attention. Don't drive tired or under the influence of whatever. Take breaks. Eat. There is no fire, you'll get there in good time. Don't drive like an idiot, there's enough of them out there already.
A special note about motoring around truckers. Please be careful around big semis or trucks. Truck drivers have a hard enough job already; long hours, heavy and difficult rigs to stop or manoeuvre, arduous schedules to meet. So be understanding of what they are dealing with and act accordingly. Give them lots of room, allow them to pass easily, stay way back when following from behind. It's mostly for your safety, I mention this.
3/ Be prepared. Got this one right from Boy Scouts, and it still rings true. Why? Finangle's corollary to Murphy's Law states; "Anything that can go wrong, will - at the worst possible moment." Like out in the middle of nowhere during a blizzard. Make sure your vehicle is safe and well maintained, to avoid roadside breakdowns. Make sure you are prepared with survival gear, if need be. Be ready.
I apologize if I sound like I am lecturing. But I must admit, I am. Somewhere along the line, a lot of people lost their sense of common decency, and took up a "Just look out for me" type attitude. It's a shame. It doesn't work. We are all in this world, together. We all effect each other. So if you feel up to it, try committing the occasional, random act of kindness. If enough of us did, the world could be a different place, wouldn't it.