The idiom as follows introduces the answer to an asked or unasked question. It always ends with a colon.
The Roman alphabet reads as follows: A, B, C, D....
The song goes as follows: "This land is your land, this land is my land..."
The criminal charges were as follows: grand theft auto, first degree murder, and whistling in class.
As follows is never necessary. All the above examples would mean the same thing without it: The criminal charges were grand theft auto...