by Lee Hamilton

As Mario Cuomo said, politicians campaign in poetry but have to govern in prose. Now we have a president-elect who campaigned in tweets … but still will have to govern in prose.

Donald Trump showed great skill as a campaigner, steering his campaign past a slew of professional politicians who underestimated him at every turn. Now the test is whether he can govern — that is, whether he can run the United States government, conduct foreign policy in treacherous times, and reshape domestic policy to fit his goals. This requires a very different set of skills from those he showed before the election.

So, like a few thousand other Americans, I’d like to give him some advice. Not on the substance of policy itself — that he’ll handle himself — but on how to be effective at achieving what he’d like to achieve.

First, he has to set priorities. During the course of the campaign, according to The Washington Post, Donald Trump made 282 promises. He is not going to be able to deliver on them all.

So he’ll need to set out his priorities with clarity and force. As the head of a vast federal establishment, clarity of objectives is crucially important in policy implementation. He cannot afford to sow confusion. Though this president-elect prides himself on unpredictability, conducting policy in an unpredictable way is the mark of a rogue state.

Unpredictability creates doubt about what he wants to achieve — both on Capitol Hill and among the vast number of people and agencies charged with carrying out his policies — which in turn produces a race by elected officials to fill the clarity vacuum with their own agendas and prevents frontline agencies from planning. Many Americans and foreign governments have already been unnerved by the unexpected Twitter messages coming from President-Elect Trump; this will only make his job harder once he takes office.

Second, the president-elect must fix his conflict-of-interest challenge. Because of the extraordinary extent of his business interests, he has an unprecedented number of potential conflicts for a U.S. president. He will be negotiating policy with many people, agencies and countries where he or his business partners have a bottom-line stake in what happens.

If he does not fix this before he takes office, conflict-of-interest charges will dog him throughout his presidency and weaken, if not cripple, his effectiveness. He has to protect himself from charges that his actions as president are influenced by his personal financial interests.

It won’t be enough to put everything in a blind trust controlled by his children. As Newsweek recently pointed out, “every nation on Earth will know that doing business with the Trump Organization will one day benefit the family.”

Third, President Trump will need to keep his majorities united. Given Republican dominance of Capitol Hill, he’s in a strong position to get things done. But he’ll have to keep his fellow Republicans on his side. Some Republican leaders are already separating themselves from his attack on the CIA analysis of Russian interference in the election. Showing respect for, and reaching out to, GOP lawmakers will matter.

So will considering a variety of different views and treating them with respect — which is how a pluralist democracy works. Knowing how to work cooperatively and accessibly with potential allies on Capitol Hill and throughout the D.C. power structure will be crucial to making his priorities a reality.

Finally, in order to do this, it’s not enough simply to say “I want this.” He has to take seriously the role of facts in the deliberative process. Members of Congress and others need to be able to defend their support for politically difficult proposals — and they cannot do this without factually based arguments.

Accurate information is necessary to make sound judgments about policy. Trump’s decision not to regularly hear information from intelligence officials is worrisome. For a president to succeed, he needs to interact in a measured, sensible, reassuring way, and supply his allies with solid analysis and information, not guesses, instincts, opinions, and debunk-able theories.

A president who sets clear priorities, removes all doubt about potential conflicts of interest, and works responsibly with his allies on fact-driven policies can make good progress and achieve his goals.

LEE HAMILTON is a senior advisor for the Indiana University Center on Representative Government; a Distinguished Scholar, IU School of Global and International Studies; and a professor of Practice, IU School of Public and Environmental Affairs. He was a member of the U.S. House of Representatives for 34 years.