how do I get out of a dating thing?

I met this guy recently. He doesn't go to my school we have no other connections or anything. We went on a "date" if you can call getting coffee a date and walked around. He kissed me which is fine but he kept doing it and he was really cheesy and stuff like that (not that any of that really matters). I just moved to a new city, I have multiple mental illnesses, and Im still not even sure I like guys. I just have a lot going on right now and I am starting to realize that I shouldn't be getting in to a relationship. Its not good for me or him. He's supper nice and I would love to be friends but I have never really done this and I don't know how to tell him. Can I tell him over the phone or txt because we only went on one date? Do I go on the date he just asked me on and let him pay for me when I am about to cut him off? Or do I do it at the beginning of the date? and then what after? do we still go on that date or do we just hug and go our separate ways? I am so confused! I would appreciate any help.