Never kiss a shark on the lips.
Always wear a seatbelt. Except for when you're not in the car.
Go ahead and bring that knife to the gunfight, but bring a gun too. That way when everyone's out of bullets, you'll have an edge.
Don't eat poison. That stuff's poisonous.
Never tell secrets to a spy. The hard part is knowing who the spies are. So if someone comes up to you and says, "I'm a spy - tell me all your secrets!", you should resond, "No, thank you". They won't be mad, because you were at least polite about it.
If someone points a gun at you and says, "Give me all your money!", you should comply...but ask if they accept checks.
Don't play in traffic. Parks are safer and more fun, assuming it's not one of the new ones with no swingsets.
Give me some safety tips!