At the front will be the Special Relationship Group, drawn from the regiments and units with the closest bonds to Prince Philip, including the Intelligence Corps, 4 Scots, the Grenadier Guards, the Royal Gurkha Rifles and the Royal Marines.
Carrying the Guidon for the Queen's Royal Hussars will be Warrant Officer Alastair Walker, he was serving in Iraq in 2006, when he met the Duke, who was then aged 85, who had paid a surprise visit to the troops.
WO2 Walker said: "I found out I was getting promoted, my first promotion to Lance Corporal, and our Colonel in Chief, Prince Philip, would be actually presenting that to me.
"So, as you can imagine, to get your first rank is a huge, huge honour, but to get it from royalty really made it even more special.
"I wasn't sure of his age at the time but to travel all that way to a very dangerous place at the time, it meant a lot to the soldiers out there," he added.
WO2 Walker, like many of the soldiers taking part, is tirelessly preparing – tailoring uniforms, polishing medals, brass and boots in an attempt to get it right on the drill square.
Sergeant Bugler Jamie Ritchie, I/C Corps of Drums, Royal Marines, is leading four buglers in playing the piece of music in St George's Chapel on Saturday.
The Royal Marine, from Dundee, will also wear a medal he received personally from the Duke after serving in Afghanistan, and spoke about the great care Prince Philip took to connect with as many personnel as possible.
"In 2012 I was deployed on Operation Herrick 17 with 40 Commandos. On return to the UK our medal ceremony was in attendance by Prince Philip, he was the VIP," he said.
"There was upwards of 300 people on that parade and each person got to chat to him for a little while and receive their medal."
Sergeant Ritchie stressed that preparations for the funeral were thorough and those taking part are aware of the "pressure" to perform well.
"It's going to be an enormous amount of pressure," he said.
"It's an incredibly important Last Post. There's four people playing it, we've rehearsed, we've practised, we've fine-tuned everything down to the millisecond to make sure we perform a superb Last Post."
All public elements of the funeral have been cancelled.
The event will be televised and will take place entirely within the grounds of Windsor Castle, a Buckingham Palace spokesperson said.