There are a lot of nutty drivers that will be sharing the road with you. Defensive driving will keep you alert for the unexpected.

Defensive Driving Tips
Always wear your seatbelt
Give yourself an out
As you drive keep escape route open to avoid trouble
Keep your eyes moving
Check your mirrors every few seconds.
(Know what is on both sides of you and behind you at all times)
Get the big picture
Do not follow any vehicle to closely, stay back and see it all.
Make sure the other driver or pedestrian sees you.
This can be done by making eye to eye contact.
Be aware of your speed and conditions.

Defensive driving is the best offense of arriving alive.