From Emanuele Feronato: "In Goat Rider you simply have to ride a goat with a weird set of characters including an elephant (yes, there should be “something” in the water BeaverTap guys drink).
Start with a tap/click, then tap and hold when the goat is red walking to the right, release when it’s white, walking to the left. If you fall down, then reload the page to restart."