Stick to your guns, but don’t fall for it. Be prepared, but not scripted. Talk to him, but don’t lose your cool. Embrace your identity, but don’t start with it.

As Kamala Harris prepares to face Donald Trump in a debate tonight for the first and possibly only time in her abbreviated presidential campaign, Democrats who have advised previous nominees have plenty of advice on how to handle an opponent whose core political skill is attacking and humiliating. The task, they acknowledged, is a tricky one: If President Joe Biden’s goal in the June debate with Trump was to demonstrate that he was fit to serve another four years in the White House — a test he famously failed — Harris goes into this contest needing to reach a much higher bar. She must lay out her vision and convince voters that she’s ready to be commander in chief, all the while remaining calm as Trump tries to shock her.

“Her goal is to be presidential and resist his attacks and keep reminding people about her body: Let’s not go back,” Jim Messina, who managed Barack Obama’s 2012 re-election campaign, told me. “That’s easier said than done.”

Watch: The candidates prepare for the debate

Trump, Messina predicted, “is going to be very mean to her and steamroller her.” Her biggest challenge, he said, will be deciding which punches to respond to and which to ignore. “Don’t go after every punch,” Messina said. “Sometimes you just have to shrug it off and look at the camera, look at the country and say, This is where I’m going to take us.”

Bob Shrum, who helped both Al Gore in 2000 and John Kerry in 2004 prepare for their debates against George W. Bush, offered similar advice. “Don’t lose your temper,” he told me he would advise Harris. “Don’t feel like you have to answer things that aren’t important and that people think are ridiculous.” As an example, he said, Harris should ignore Trump when he calls her a communist, which he characterized as an outdated line of attack that voters would find “absurd” given that Harris’s economic views fall well within the Democratic Party mainstream.

Harris excelled in previous debates, during her successful bid for California attorney general and in the 2020 presidential campaign. Her critique of Biden’s record on desegregation (“That little girl was me”) marked the high point of her short-lived bid for the Democratic nomination. Harris’s sharp response to an interrupting Mike Pence — “Mr. Vice President, I’m speaking” — provided one of the few memorable exchanges of a running-mate debate that might otherwise be overshadowed by a fly on Pence’s head.

Still, she’s never faced someone as tough or unscrupulous as Trump. The former president “is the best counterpuncher in modern political history,” Messina told me. “This is a better format for him than it is for her.” To other Democrats I spoke with, though, that rosy assessment of Trump’s skills sounded suspiciously like the kind of expectation-raising campaigns try to raise in the run-up to big debates, to help their candidates outperform their expectations. Harris’s campaign, for example, has complained that the vice president will be “fundamentally disadvantaged” because neither ABC News, the network hosting the debate, nor the Trump campaign would agree to a request that the candidates’ microphones remain on during the debate; as during the Biden-Trump debate in June, the microphones will be muted when the candidates aren’t speaking, potentially preventing viewers from hearing Trump if he tries to interrupt Harris. Trump’s frequent interruptions of Biden during their first 2020 debate went down badly, leading to one of Biden’s quicker responses when he told Trump, “Would you shut up, man?” Democrats believe Trump has even less discipline four years later.

Shrum said he thought Harris would be fine either way: Trump “behaves badly in ways that send messages about his character, and those are not good messages.” Shrum added that he knew he had to raise expectations for Trump’s performance, “but I’m not going to do that.”

With Biden off the stage, many Democrats are hoping the debate will expose Trump as the weakened candidate, a 78-year-old who babbles even more than before and struggles to formulate a coherent thought. “She’s going to have to get out of Trump’s way,” Ashley Etienne, who served as Harris’s communications director during her first year as vice president, told me. “Let Trump be Trump and not (debate) him point by point, back and forth.” That could be tough for Harris. “To some extent, she’s going to have to deny that instinct of persecution,” Etienne said.

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Trump will likely try to tie Harris to Biden’s unpopular economic stewardship, blaming her for inflation. Rather than getting bogged down in a defense of the president’s policies, Etienne said, Harris should quickly shift to her vision for the future and a critique of Trump: “Her main thing is not to defend her record. It’s to talk about Donald Trump.”

Democrats I spoke with expect Harris to hold back when Trump launches racist or sexist attacks at her, as she did after he said in July that she “just happened to turn black” a few years ago, suggesting she was trying to use that part of her identity for political purposes. When CNN’s Dana Bash asked her about the comment in an interview last month, she responded, “Same old tired playbook. Next question, please.”

Aimee Allison, an Oakland, California-based founder of a political group that advocates for the empowerment of women of color, told me that Harris should strike that exact tone during the debate. “Don’t keep giving vent to Trump’s obsession with identity,” Allison said. “He wants to use the age-old white male power grab, but by not considering that, he has very little power among the people who will vote for Kamala Harris.” She praised Harris for a campaign that didn’t center the history-making nature of her candidacy in the same way that Hillary Clinton’s “I’m with her” slogan did in 2016. “We’ve grown as a country,” she said.

How much the country has grown, however, remains an open question. Candidates in televised debates are scrutinized almost as much for how they look when they’re not talking as for what they say when they are. Think of George H.W. Bush’s glance at his watch in 1992, Gores’ deep sigh in 2000 and Biden’s wide-eyed stares in the June debate with Trump. Black women are even more scrutinized for their body language, Etienne said. “She knows it. She’s used to it,” she said of Harris. “I would just caution her to be aware of her nonverbal cues.”

Trump has downplayed Harris’ intelligence, and his campaign has teased her for agreeing to few formal interviews and press conferences, implying she is weak in situations she can’t anticipate. Harris stumbled in interviews early in her term as vice president, and her public image only recovered when she launched her campaign in July. Those who have worked with Harris, however, say Trump knows her only as a right-wing caricature. Tonight’s debate will be the first time they’ve met in person. “She’s good when she gets a little fire under her,” Etienne said. “I don’t think he’s ready for that.”