How do I get the "Say Hi to the Internet" achievement?

The lost Hollywood star can be found at the coordinates X: 619.7, Y: 559.4 (see top right corner of the world map). This is at the beach of one of the northern islands. You can go there shortly after the game starts. Stay at the beach and look for two dead people that are hanging on a tree. There is a man burried in the sand and you can only see his head. Go to the burried man and press Square.

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