Hillary Clinton Debated Trump. Here’s Her Advice for Kamala Harris.

Hillary Clinton has as much experience as any Democrat in debating Donald J. Trump.

The 2016 presidential campaign, when she was her party’s nominee, included three of the six general-election debates Mr. Trump has participated in. Those faceoffs went a long way toward shaping the country’s vision of his candidacy and what he would be like as president.

Mr. Trump, of course, went on to win the 2016 election — an outcome that still haunts Democrats.

When Mrs. Clinton called this week to discuss her old debate coach, Karen Dunn, who is helping out Vice President Kamala Harris this time around, I took the opportunity to ask about her experience on the debate stage with Mr. Trump.

“The consensus was that I won all three debates and that I was well prepared,” Mrs. Clinton said.

Here are excerpts from our conversation, which have been lightly edited and condensed.

What do you remember about your own preparations to debate Donald Trump?

It was the first debate when Trump literally ridiculed me for preparing. This was not something we had thought about beforehand, because who thought we could be ridiculed for preparing for a presidential debate in front of 85 or 90 million people?

So basically I said, yeah, I did prepare. And I’ll tell you something else I prepared for: I prepared to be president. Because I had the confidence. I knew the material. I felt comfortable. I also knew I had to brush Trump back and not let him be the center of attention all the time.

What advice do you have for Kamala Harris as she prepares to debate Trump?

She’s proven to be a good debater, both in her races in California and in her debate with Mike Pence. So I think she needs to be prepared enough that she feels really comfortable going on both offense and defense against Trump, because there’s a lot to cover with him.