How to break up with him, the second time?

I dated this guy, and I thought that I truly liked him. It just ended up being nothing. And so I broke up with him. Then after a couple of months we got back together and i tried to like him, i just can't. I don't like hurting people and i need to find a way to make a clean break up, i don't have the guts to do it in person. Can someone tell me how to do this?How to break up with him, the second time?
i know聽 the guts聽 part may be hard (i am聽 the聽 same way) i feel way too聽 bad聽 ...聽 and dont wana聽 do it in person.. but ur聽 partner聽 will b madder if its over the internet or something (experience.) doing this in person is best...