Staking a career as a Commonwealth Bank executive, she ran for the seat of Willoughby in 2003 against a popular local mayor.

In the teeth of difficult polling, she took to the Glad-mobile.

The white delivery van plastered with posters calculatedly omitting her last name (it's pronounced Ber-a-jik-lee-en), helped her sneak over the line by fewer than 150 votes, in a result that wasn't known for days.

At the last state election, she nearly tripled the vote of her rival and claimed a two-party preferred vote of 75 per cent.

On Monday morning, Ms Berejiklian, the kindergartener who barely spoke English but became the dux of North Ryde High, will transform again, from the quintessential local member, to the Treasurer in charge of a $70 billion budget, to NSW's 45th premier.

There's a lot the state is yet to learn about the Masterchef-loving former checkout chick. (Her aisle had a cohort of loyal customers who noticed she would mistakenly scan artichokes as much-cheaper chokos).

Her colleagues believe her authenticity will be the key to connecting with voters as premier, after years of favouring diligent work to conspicuously building a profile.

"People may know that NSW is number one again," one senior NSW Liberal says. "But there's a bit of a sense that not everyone is sharing [the proceeds]. She's the perfect person to tell that story."

In more than one way Ms Berejiklian is the photo-negative of Premier Mike Baird, the Kings-educated son of a former Liberal Minister.

She was the daughter of a welder and nurse who came to Australia from Jerusalem and Syria in the 1960s. She spoke English only occasionally before the age of five. Her mother encouraged her to speak up in class whenever possible to practise the language.

Friends say her Armenian heritage influenced her progressive brand of Liberalism.

But she counts a sit-in demonstration in the principal's office of her public high school as lighting the fuse on a career in politics that has often seen her stake out tough positions. (The school closure was reversed.)

"She was Young Liberal president when Pauline Hanson was first on the scene," says North Sydney federal Liberal MP and friend of two decades Trent Zimmerman. "She was adamant that the party had to take a stand against racism. She took the view the best way to counter extremism is to speak out."

(The Left-faction stalwart has also broken with other party members, including Mr Baird, to vote for same-sex adoption and stem-cell research.)

Friends describe a woman of incredible discipline and who starts her days reading ministerial briefings over breakfast and who is often caught checking emails under the dinner table.

But she never misses Sunday visits with family and is extremely close to her two sisters and six godchildren.

She made her name as transport minister, once thought to be the cursed portfolio of NSW politics.

"She really is the most determined, hard-working person I know," says Liberal MLC and President of the NSW Upper House, Don Harwin. "And yet I struggle to think of anyone who doesn't like her."

But even former premier Barry O'Farrell, perhaps her biggest backer in politics, conceded she didn't put herself forward enough.

Opponents sense a weakness. Even before she's been sworn in, attacks from shock jock Alan Jones and Labor, which is counting her understated style as a weakness, have already zeroed in on the question of whether she's ready for the top job.

But her colleagues, who coalesced around her in little more than a day, say they have little doubt.

"Once she's made up her mind, she doesn't waver," Mr Zimmerman says.  

How Monday's events will unfold

●The Liberal party room will convene for a meeting at 10am on Monday.

●Premier Mike Baird will make his farewell address as Premier to MPs and declare the party's leadership positions vacant and call for contenders to self-nominate.

●Gladys Berejiklian is expected to nominate unopposed for the party leadership and therefore become NSW's next Premier. Current Finance Minister Dominic Perrottet is expected to nominate unopposed to become the party's deputy leader.

●Ms Berejiklian will assume chair of the meeting and appear before the Liberal party room for the first time as its leader.

●Ms Berejiklian will be sworn in as the 45th Premier of NSW on Monday afternoon.

●The full cabinet of the Berejiklian government will be announced at a later time.