Wedding guests will begin to arrive – by coach, no less – from 9.30am until 11am, and will walk over to the South Door of St George's Chapel. Prepare to spot assorted Suits stars, Priyanka Chopra, Jessica Mulroney and the Beckhams.

Keep your eyes peeled from 11.20am as members of the Royal Family start to arrive at the Chapel, some on foot, others by car.

Prince Harry will arrive at St George's Chapel by foot, accompanied by his best man the Duke of Cambridge, and will enter via the West Steps. Here, they'll take the time to greet the members of the public gathered in the Castle precinct, including the charity representatives positioned at the Horseshoe Cloister (just outside the Chapel).

At around the same time, Meghan and her mother, Doria, will leave their overnight location and travel to the Castle by car, passing through the Long Walk where members of the public are expected to gather. They'll briefly stop at the Castle, allowing Doria to travel on to the Chapel while Meghan is joined by bridesmaids and page boys ahead of her big entrance to the Chapel.

After Thomas Markle confirmed that he would no longer be walking his daughter down the aisle, having suffered a heart attack last week, it's assumed that Doria will accompany her daughter.

The wedding service itself will take about an hour, with a full order of service set to be unveiled to the public on Saturday morning. We already know that Lady Jane Fellowes, Harry's aunt and the elder sister of the late Princess of Wales will give the reading. All three of Diana's siblings will attend the ceremony, and Harry and Meghan have expressed happiness that they'll be able to celebrate her memory on the day.

Once they've officially tied the knot, the first thing that Harry and Meghan will do is to greet the 200 representatives from Prince Harry's chosen charities, who'll be gathered in the Horseshoe Cloister. In doing so, the couple are acknowledging how important these organisations will be in their future work; according to the Palace, they are 'delighted that these people who will be such an important part of their official work in the years to come will be the first people they see after the wedding.'

Then, close family members will gather on the Chapel's steps to wave the couple off, as it's time for Harry and Meghan to step into their carriage (that's the same Ascot Landau that Pippa Middleton rode in at Will and Kate's wedding, in case you needed a refresher) and embark on a 25-minute procession around the castle and town. Hopefully neither of them have previous history with RSI, because all that royal waving could get very tiring. Meghan and Harry's guests will then file out of the church to catch the start of the carriage procession, before heading on to St George's Hall for the reception.

For all the national excitement, the wedding is a private event, and after the carriage procession, there won't be much left for us to see. The last thing that we'll be able to catch will be the moment that the bride and groom leave the Castle for Frogmore House, where the evening reception will take place.