In a straight and flat position, if you feel that your direction pulls to the right or to the left, you may have a tire trying to deflate (slow puncture). Stop as soon as possible to check, and if necessary, change the wheel.
Beware of children on the edge of a road, even (and especially) if they are held by the hand. Systematically make a distance and, if necessary, slow down.
Pay attention to the ball that crosses the road, there is always a child who follows!
About the trucks, don't expect that they have the same reactions than a car. In particular, do not attempt to pass him by force, he will not be able to stop!
On a country road, do not hesitate to take a look at the fields on the right and left side of the road before you. Perhaps, you could see the animal that will cut you off the road.
When you pass near a car accident, slow down to avoid the dangers, not to watch the (sad) show!
If you need to brake in emergency, try to take a look in your rearview mirror. If the vehicle that follows you is too much close, try replacing the braking by an avoidance procedure (not always easy).
Pay attention to dead leaves on the road. A carpet of leaves, especially wet (and they are often wet below), is as slippery as a plate of ice!