New UK prime minister: What can Liz Truss expect on her first day?

For most UK prime ministers, day one in the job starts with a trip to Buckingham Palace to be formally appointed by the Queen. For Liz Truss it will instead be a 1,000-mile round trip to meet Her Majesty at Balmoral Castle.

But what happens at that meeting and what can she expect to follow on her first day as prime minister? We spoke to people who have been inside Downing Street and asked what else they remembered from day one.

Whether it is in Balmoral or Buckingham Palace, the new prime minister will be appointed through the same ceremony - a tradition called "kissing hands".

In his autobiography Tony Blair - who was operating on only one hour's sleep following his election victory - admits to being a bit confused when a royal official told him "you don't actually kiss the Queen's hands in the ceremony of kissing hands. You brush them gently with your lips".

"What on earth did he mean?"Mr Blair writes. "Brush them as in a pair of shoes, or touch them lightly?

"While I was still temporarily disconcerted, the door opened and I was ushered in, unfortunately tripping a little on a piece of carpet so that I practically fell upon the Queen's hands, not so much brushing as enveloping them."

Having been formally appointed as prime minister, the new leader heads to 10 Downing Street - their new workplace and new home. Here they will make their first prime ministerial speech with the aim of explaining what they want to do in government.

Margaret Thatcher promised to bring "harmony...where there is discord", Gordon Brown vowed to "try his utmost", Theresa May spoke of tackling "burning injustices" in society, while Boris Johnson warned that "the doubters, the doomsters, the gloomsters" would "lose their shirts".

If a politician is lucky, they will give their speech in glorious sunshine providing a PR-friendly visual metaphor to kick off their tenure. Rain is forecast for Tuesday, unfortunately, so Ms Truss's team might be anxiously watching the weather.

David Cameron didn't have much luck. The back and forth negotiations for his coalition government, and the timing of his predecessor's departure meant the Conservative leader had to give a speech as dusk set in - not ideal for his spin doctors.

The new prime minister will then enter through the famous black door to be greeted by Downing Street staff, who traditionally line up to applaud their new boss. Usually it is all smiles, but not always.

When he arrived, Mr Blair noticed one of the secretaries was in tears. Lord Robin Butler - the most senior civil servant at the time- recalls that Mr Blair asked if she was ok. "Well, Mr Blair, you are welcome," she replied "but I did so like that nice Mr Major [Mr Blair's predecessor]."

In his book about New Labour - Servants of the People - journalist Andrew Rawnsley recounts an extended, more brutal version of the story - Mr Blair says he is sorry to which the weeping employee replies "You're not sorry at all, you meant this to happen."

Mr Blair himself admits that by the time he had finished meeting the staff he felt "a right heel... coming in and creating all this distress. Needless to say, I got over it."

Caroline Slocock was a private secretary in the civil service when John Major took over from Margaret Thatcher.

"It was a rollercoaster of a day," she says recalling how staff had to adjust to the different style of their new boss. He was practising cricket strokes and bowling techniques in the office," she says. "He was definitely being playful, whatever else Margaret Thatcher was, she didn't tend to be playful."

Introductions done, a prime minister is then taken into the cabinet room.

Gus O'Donnell - former head of the civil service - says this is the point he remembers David Cameron "putting his head in his hands and thinking 'Oh my god, what have I let myself in for?'."

There is not much time for anxious introspection as a prime minister must immediately begin appointing senior ministers, some of whom can prove to be surprisingly elusive.

Theresa May's adviser Katie Perrior recalls going on a hunt to find Boris Johnson "who nobody could find anywhere".

"I suspect he thought he would be without a job and was as surprised as the rest of us when finally he was appointed foreign secretary."

Mrs May's team also faced the challenge of trying to put together her new team while the old team were still wandering around the building - that included George Osborne who had been chancellor under Mrs May's predecessor David Cameron

Ms Perrior says he only discovered he was about to lose his job "when a press officer squealed it out as she read the list… just as he walked by".

"I suspect he knew what was in store for him in any case."

Even when you are offering someone a job, don't expect them to be grateful. Bernard Donoughue, who advised the Labour Prime Minister Harold Wilson, was sent to find Roy Jenkins to offer him a role.

In his diaries, Lord Donoughue writes: "I meet him in the corridor and say that HW [Harold Wilson] would like to see him.

"Roy explodes in an extraordinary fashion, shouting 'You tell Harold Wilson he must bloody well come to see me and if he doesn't watch out, I won't join his bloody government'."

Dealing with angry colleagues is to be expected for a prime minister on their first day. Struggling to find a snack is not. With no café, no staff kitchen and no time for the Blairs to have done a quick shop - trying to find food proved surprisingly tricky in 1997.

"It was a real problem," says then-adviser Jonathan Powell, recalling the difficulties of trying to get sandwiches through the "security apparatus" at the front gate of Downing Street.

"I remember trying to order some pizzas at one stage and having them blown up by the security people who were suspicious they were bombs."

In a perhaps overlooked achievement of the New Labour government, Mr Blair's advisers introduced a coffee machine - although Mr Powell says there was a battle persuading the Downing Street staff to make "new fangled coffees" such as espressos.

Throughout the leadership campaign, civil servants will have been monitoring the candidates' various policy pronouncements and preparing advice on how the plans of the incoming candidates could be put into place.

This advice is turned into briefs which are presented to the prime minister on their first day in the job. "It is a very big pile of paper," says Lord Butler.

"You want them [the new prime minister] to feel that everything has been thought of."

At some point during their first few days, the prime minister will have to do something that will put everything else into perspective.

They will sit down and write letters to the four commanders of the UK Trident submarines with instructions about whether they should retaliate in the event the UK suffers a nuclear attack. The letters are stored in a safe on board the submarines, and only opened if contact with the UK is lost.

James Callaghan - prime minister from 1976-1979 - is the only former leader to reveal what he would've done in the event of a nuclear attack.

"If we had got to that point where it was, I felt, necessary to do it - then I would have done it," he told a BBC documentary in 1988. "I've had terrible doubts of course about this. And I say to you that if I had lived after having pressed that button, I would never, never have forgiven myself."

In 2013, political historian Lord Peter Hennessy told BBC Radio Four: "This is the moment they know what being prime minister is all about - no other job can prepare you for this."