off
Much of the time this concept is just fingerspelled.
The fingerspelled form of "OFF" uses a strong quick movement. (lexicalized)
This would be a good version to use in the sentence, "Take your shoes off," which would be signed: "SHOES O-F-F."
OFF: (fingerspelled version)
Power down a computer. Turn off a computer.
You would first sign "COMPUTER" and then do this sign:
In context you could use the above sign to also mean: "Turn off your headlights."
The general sign for "OFF." In "Signed English" this sign means the same as the English word "off."
But in ASL this sign is generally only used to show a blanket, tarp, piece of paper, or other flat object "blowing off," or "coming off."
Sometimes I see ASL users doing this sign with little kids.
In those instances it is being used as "motherese." (The specialized type of communication that takes place between adults and small children.)
Instead of using this sign, you should ask yourself, "Is there some other way to communicate the concept "off?"
OFF: "knob version." Turn a gadget off.
OFF: "Switch version." Flip a switch off.
"Turn off the lights."