how can I let him off easy without hurting him? HELP

So I just got out of a year and a half relationship about two months ago. Then started talking to this boy at my seasonal job. 
Well we started hanging out and making out and we kinda just became a thing. But it happned quicker than I wanted it to be. 
And now I want out. I need time for me. Away from boys. But I don't know how to tell him without hurting him because he's so into this relationship and I'm not all the way into it. Yes I'm loyal to him. But I just wanna do me . Y'know ? So what should I tell him ?