Donald Trump, famous for firing people, now has to make his most important hire — a running mate on the Republican presidential ticket.

Trump says he doesn’t yet know who he’ll choose, but a look at his career as real estate developer, reality TV host and political candidate gives some clues as to how he’ll make his decision and what type of person he might tap.

Although his campaign has yet to establish a selection committee — except to say thatBen Carson would be on it — Trump says he wants an experienced politician who can help him with Congress, which doesn’t narrow things down much.

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What is clear is that Trump usually hires by gut, not committee. He values capability above experience, aggressiveness above credentials and loyalty above all. Unlike many candid bosses, he accepts candor from employees.

If you’re good-looking, that’s good. If you’re family, that’s best.

But Trump isn’t appointing a construction manager or anointing an Apprentice winner.  “This is a whole new process at a whole new level,’’ says Wayne Barrett, a formerVillage Voice reporter who’s investigated Trump’s business deals. “He has an eye for business talent. Whether he has one for political talent is another question.’’

The Herald: PLANS: US business tycoon Donald Trump. Picture: Andrew Milligan/PA.

Michael D’Antonio, author of a Trump biography, Never Enough, wonders how Trump will reach his decision: “He’d probably be best served by a sober, deliberative process, but when has he ever had to hire someone who mattered this much?’’

Here are the types of people Trump traditionally likes to hire:

Novices: Trump takes chances on unknowns. Matthew Calamari, the Trump Organization COO, was working security at the U.S. Open tennis tournament in 1981 when Trump spotted him evicting some hecklers and hired him to handle his own security.

Such hires are less expensive and more loyal, says D’Antonio: “He doesn’t require first-tier people. I think he’s kind of uncomfortable with them. If he can pluck you from a less prominent place and pay you well, he prefers that.’’

Trump’s original campaign staff, which helped pull off one of the biggest upsets in U.S. political history, consisted of “people who would never have been hired to do what they're doing by a campaign that was sane," Stuart Stevens, strategist for Mitt Romneyin 2012, told The Hill earlier this year.

Corey Lewandowski, the campaign manager, had never run a successful statewide race. Hope Hicks, a spokeswoman, was doing Trump corporate PR and had never worked for a political campaign.

That’s fine with Trump. “He wants diamonds in the rough,’’ says Gwenda Blair, a biographer.

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Women: Trump, supposedly a cave man when it comes to the opposite sex, has hired many female executives. They include the late Norma Foerderer, his top assistant, and Barbara Res, construction manager for Trump Tower.

Naming a woman head of a big construction project was unheard of in 1980. Res says today that when Trump hired her he told her that “men are better than women, but a good woman is better than 10 men.’’

His logic: A woman who’s succeeded in a sexist system had to be outstanding.

Insiders: Trump likes to hire and promote people he knows. “They don’t have drug problems, they don’t have alcohol problems,’’ he told Bloomberg last year. “I would rather take guys at a lower level and move them up than hire people that you have no idea who they are.”

Calamari rose from security chief to COO. Foerderer, hired as a secretary, became executive vice president. Trump’s social media wizard, Justin McConney, is the son of the Trump Organization controller and has been with Trump companies since 2009. A small San Antonio firm that’s worked for Trump since 2011 was hired to build the campaign website.

Trump took a liking to Res after he saw the 31-year-old engineer stand up to an architect at a meeting on Trump’s first big project, the conversion of the old Commodore Hotel at Grand Central Terminal into a Hyatt. Next thing she knew she was sitting in his living room, listening to his plans for Trump Tower.

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Relatives: Trump always has relied on family. Ivana, his first wife, helped manage his Atlantic City casinos and ran the Plaza Hotel. Their children — Ivanka, Donald Jr. and Eric — now largely run the Trump Organization.

Most corporate websites have biographies of key managers. The Trump Organization’s doesn’t mention anyone whose last name isn’t Trump.

Truth-tellers: Ronald Kessler, a journalist who met Trump while working on a book about Palm Beach, says that he “expects candor in people he hires. It’s the one thing that really stands out.’’

Up to a point. Once a decision has been made, notes Blair, he expects complete loyalty — “someone who’ll jump when he says jump.’’

Adversaries: “I often hire people that were on the opposing side of a deal that I respect," Trump told Newsday in 1989.

In the early ‘80s he sued New York City Housing Commissioner Anthony Gliedman personally for blocking a $25 million tax abatement for Trump Tower. But in 1986, after a lunch in Little Italy, Gliedman agreed to join the Trump Organization and leave the administration of Mayor Ed Koch — Trump’s arch-enemy.

Lookers: Trump cares about a prospective hire’s hairstyle, weight and attire. The winning Apprentice contestant often was best looking. Hicks, the spokeswoman, is a former model.

For Trump, attractive equals successful, says D’Antonio: “It’s very important that someone look the part.’’

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Characters … as in stories: Trump likes hires with a good back story. Gliedman’s showed Trump’s willingness to bury the hatchet. Res’s showed his focus on talent.Apprentice winners were rewarded with impressive-sounding development or managerial jobs (although they were often relegated to service in the Apprentice/Trump publicity juggernaut).

Trump “believes in the power of story,’’ says D’Antonio, “especially a surprising one.‘’