How can I let a guy know I'm just interested in him as a friend?

Question

There's this guy that thinks I like him, but I don't, I just like him as a friend. What can I do to show him that I like him as a friend only?

Answer 1

tell him casually "your such a great FRIEND (not yelling but emphazing)".

and/or talk about other guys when with him.  

Answer 2

tell him flat out that you like him as a friend but your flattered that he liked you