How do guys want to be turned down?

I know no guy wants to be turned down. No one does. And I don't want you to think that I can't deal with my own relationship issues.

But this question has been in my mind. From a guys perspective how do they want to be let down? I have had to let down several of my guy friends in my life because I was not attracted to them like that. But I am now wondering the best way to go about it. Right now I have a friend that just doesn't seem to get the hint. He has no reason to think I am interested, I feel I have made it clear. I don't even call him or anything. The only thing I have left to do is outright walk up to him and say 'I'm not attracted to you' because the subtleties aren't getting across. How do guys want this message brought to them? That is in a way that I can remain on speaking terms and hopefully still friends.

I want to hear from girls and guys here, tell me any experiences you've had.

Thanks

Guys want you to be straitforward, we don't want you to beat around the bush. Just be straight with him.