There could be a fire, a gas leak, a bleeding or choking child, or other emergencies you need to be able to handle to keep yourself safe and the children you are watching.
Baby sitting is a big responsibility.
When you take a baby sitting job you are saying to the parent, I am capable of handling an emergency if one happens while you are gone. If you are baby-sitting and you smell smoke or fire, get everyone out of the house. Do not try to find or put out the fire yourself. Forget all things, like shoes or your belongings, just get everyone out safely. If you remain calm, but act quickly, the children will trust you and follow you.