5. “I’m sorry. I think you’re great, but I don’t think we could work as a couple.”
It’s also not a bad idea to be direct about how you feel. He will be disappointed that it didn’t work out, but also glad that you were honest with him. However, this is not something to say when you’re not sure if he likes you, or when you’re still getting to know each other, as it makes you sound presumptuous.