“It was question and answer, question and answer,” Giuliani said. “Chris had a lot of advice and was very helpful. He’s one tough debater.”
Republican National Committee Chairman Reince Priebus also attended and played a prominent part, offering guidance and suggestions on how to target Democratic nominee Hillary Clinton.
Giuliani described the conversations over salad and sandwiches as intense but informal. He said Trump sat with Christie, Priebus and his “usual group” but did not hold a mock town-hall debate.
“That’s the way he likes to do it. That’s the way he’s most comfortable preparing,” Giuliani said of the circle of friends and staff members.
Trump campaign manager Kellyanne Conway, campaign chief executive Stephen K. Bannon, policy adviser Stephen Miller and Trump’s son-in-law, Jared Kushner, were also present, Giuliani said.
Conway and Bannon were behind arranging Sunday’s smaller than usual gathering with the hope of keeping the talks free of distractions and interruptions.
Giuliani said that Roger Ailes — the controversial former Fox News Channel executive who has faced allegations of sexual harassment and who has participated in past debate prep meetings — was not at Bedminster.
“Roger wasn’t a part of it,” Giuliani said.
When asked if Trump was furious about the coverage of his 1995 tax return, which was obtained by the New York Times, Giuliani said, “No, no. He’s in a good mood and feeling very comfortable.”
“This is an entirely different debate. He’s preparing for the audience, for how to answer the questions that come up and how to deal with them,” Giuliani said. “I’ve got to tell you, I’m banking on Donald being a lot better at interacting with people than Hillary. That’s how her husband won the election.”
“There will be no looking at watches,” Giuliani added with a chuckle, referencing President George H.W. Bush’s famous glance at his watch during a 1992 town-hall debate with Bill Clinton that boosted Clinton's candidacy and left Bush being seen as disengaged.
Giuliani pointed again to Christie as someone who made clear to Trump the importance of body language and presence at town hall gatherings. “Donald has an appreciation for all of that, for the human contact side of it, and he’s pretty good at it,” he said. "He's ready."
Christie has held more than 130 town hall events since taking office in 2010 and used those often-combative sessions to raise his national profile. He also held many town hall meetings during his unsuccessful bid this year for the Republican presidential nomination.
The second presidential debate will be held on Oct. 9 at Washington University in St. Louis. It will feature questions from a studio audience and from CNN’s Anderson Cooper and ABC’s Martha Raddatz, who will serve as co-moderators.
A Trump adviser said Sunday that the candidate has blocked off time later his week for further preparation and called Sunday’s meeting one of numerous debate-related meetings that have been held in recent days.
Philip Rucker contributed to this report.