he said he's very well prepared, and then said he doesn't think he has to prepare very much. At least be honest.
"I think I'm very well-prepared," Trump told reporters during a photo op with Japanese Prime Minister Shinzo Abe on Thursday. "I don't think I have to prepare very much. It's about attitude."
https://www.cnn.com/2018/06/07/politics/donald-trump-north-korea-attitude/index.html
So, like Spanky said, you don't know how much he's been prepped up to this point.