How do I monetize YouTube videos?

How do I monetize YouTube videos?
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 What are the requirements for monetization on YouTube.

You need:

• 1000+ subscribers
• 4000+ hours of watch time in the last 12 months
• Original content that pleases YouTube (means, nothing controversial. No politics, no sex, no guns, no drugs, no rants, no pranks, no dangerous activities 
• YouTube can take many months to decide if they want to monetize your channel or not.