Google rolled out AMP officially in February 2016.
A year later, most people are still struggling to get it implemented on their WordPress websites. The only official implementation is still buggy on its own, and it does require a theme implementation to get it to work as it should.
So far, the easiest and most efficient way to get AMP rolling with zero issue is to use themes with an official AMP integration. If it’s not an option, and even if it’s not always ideal, using the right AMP plugin can help to some extent.
AMP ready themes
The list will grow with time since AMP gives a real boost on search ranking.