Fake news is also known as rumor, then the question should be what is rumor?.
Rumor is unreal,imaginative,cook-up story made up by some individuals to elevate some set of people and to downgrade some.It is a tool of propaganda mainly used by politicians just to have many people at their side than their opponent.It is also use for blackmailing in order to extort people.
HOW DO YOU DO AWAY WITH FAKE NEWS?.
 DO NOT KEEP YOUR SECRET WITH PEOPLE YOU DO NOT TRUST.
 DO NOT IMAGINE UNREAL THINGS TO EXTORT PEOPLE .
 DO NOT INVADE OTHER PEOPLE’S PRIVACY SO THAT YOU WILL NOT BE INVADED.
 STOP ALL SORT OF IMMORALITY ACT THAT CAN BE USE FOR BLACKMAILING.