How do I break up with a guy I've only been going out with him for a week?

I've been dating this guy and I'm not acting the same ever since we started going out. I'm not being fun or anything with my friends. I don't know how to break up with him.





( Don't say '; Don't break up with him.';)How do I break up with a guy I've only been going out with him for a week?
Well, lol this might not be the best answer...but I was with a guy for a week and didnt like him, there was just no chemistry...I just avoided him, and he got the hang of it after like 2 days... I'm sure thats not the right way to go about it..But hey, im not with him anymore! =)