Do it in private, away from other people. You never know how he's going to react, the tears might flow and you don't want him to be embarrassed.
I'd say as I'd wish it on me.
I'd want to be Let down kindly and honest on why it's happened.
As an extract I'd think:
Girl: Hey I'm sorry but I'm feeling hints are not good between us but I feel the only way to get better is by us not being together anymore.
Boy: Did I do something wrong?
Girl: No/yes then provide an explanation as to what it was
Tell him that you two are better off just friends. I can't tell you exactly how to end the relationship whether or not it's over text or in person but my only advice is don't leave him hanging
Tell him otis is your new boyfriend
Do it face to face and in private. Be honest but kind. And remember breaking up with him is just as fair to him as it is you. No one likes to be lead on.
just do it. You'll feel better.
I'm a guy so I don't think I can help
Sorry