You are first and foremost safest in a well lit location. In the light, they cannot touch you.
When sleeping in a well lit location it is best to cover your lower body anyways, just in case.
When in dimmer light, cover your body from toes to neck. What the light does not protect, the blankets will.
Never stare for too long into the dark, for any reason.
The shadows that the dim light casts can be just as much of a threat as the dark itself.
Shining a flashlight out into where the dim light cannot reach will only antagonize it.
Without any source of light you must cover yourself completely. Every inch of you must be concealed even if it makes it harder for you to breathe.
Don't make any noise. Even whimpers of distress will entice them. If not more so.
Do not move. It attracts their attention.
If you ever see eyes, do not meet their gaze with your own under any circumstances.
They will make noises that you will not understand in an effort to make you investigate. Don't.
Only bright light can make them go away. At this point, flashlights will make it worse because they will track the beam to its source.
They will not attack if an adult is present, but they can remain in a room even if an adult has entered and stay long after they leave.
If you drop anything from where you can no longer reach it, that thing is gone until the day returns and until then is at the complete mercy of them.
Never run. They will chase, and they are much faster.
Do not call for help unless you have absolute faith that those you call can arrive in time to protect you.