If I make a sign, can I say "Do not dispose"?

[Yxr]

Which one is correct?

"Do not dispose"
"Do not dispose of"
"Do not discard"

Thanks

[Mister Micawber]

Do not discard
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Native English teacher at Mister Micawber's

[Yxr]

Thanks.

How to say it if I really want use "dispose" ?

[Mister Micawber]

I don't know why I waste my time here. No one listens to me.
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Native English teacher at Mister Micawber's

[Milanya]

Do not despair.
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con·text - The part of a text or statement that surrounds a particular word or passage and determines its meaning.