As genocide is most likely to occur during war, one of the best ways to reduce the chances of genocide is to address the root causes of violence and conflict: hatred, intolerance, racism, discrimination, tyranny, and the dehumanizing public discourse that denies whole groups of people their dignity and their rights.
Some actions ain't supposed to escalate into something so big and deep as this, but peaceful resolutions isn't a language people understand so well. They will use force, destroy lives and properties, then turn to peace after lots of damages have been done already. Life is a struggle and the strong won't stop eliminating those who would stand on their way.