If someone else insists they have the right of way (even if technically they don’t) let them have it. That gets them away from you so if they run into someone it won’t be you.
When you come up to an intersection, even though you have the green light, always keep an eye out for folks who might not be stopping, and even take your foot off the gas as you come up to it so you can hit the brake faster if you have to.
If someone doesn’t seem to see you don’t be afraid to use your horn.
If someone appears to be driving erratically, pull off the road for a while until they have gone on their way. Again, that gets them away from you so you don’t have to worry about them.
Never drive when you are tired, angry or stressed, and never try to multitask when you are driving. If you have to, turn your cell phone off.
Don’t believe anyone’s blinker (or lack of blinker) until you actually see them turn or go straight. In other words, drive as if everyone else on the road is an idiot or worse.
And if you have car trouble get well off the road, put your hazard lights on, and if you can do it safely get out of the car and off to the side in case someone is not paying attention and plows into your vehicle.
And something I keep trying to get my daughter to do is this: read the manual that comes with the car. It tells you where all of the controls are, how to open things that need to be opened, turn on or off things that need to be turned on or off, and what those various lights mean on the dashboard. It even tells you some reasons why your car might be misbehaving.