You should place your monitor far enough from your eyes. Don't spend too much time at the screen.
Switch off the lamp leaving the room.
Don't forget to turn off the tap leaving the bathroom.
Don't use electrical apliances while having a shower.
Don't stand under a tree during the thunderstorm.
Don't swim in the river or lake during the thunderstorm.
Don't dive at the place you don't know well.
When you are in a boat don't stand up and don't move it as it can turn over easily. Put on a life jacket. Don't jump into the water from the boat.