The event will herald the festivals for the 33rd year, with more than 3000 participants from the Edinburgh International Festival, the Fringe, the Arts Festival and the Tattoo lining the streets.
Up to 175,000 spectators are expected with organisers advising people to arrive early to secure the best views.
For those who prefer to take things easy and don't mind shelling out, a series of grandstands will be set up along the route at a cost of 10 per person. Tickets are still available and will be on sale from 12.30pm today.
This year's parade will see an exceptional turnout from Edinburgh's Chinese community celebrating their country's hosting of this month's Olympics.
While Olympic organisers continue to face protests over their decision to hold the event in China, Cavalcade director David Todd said the Cavalcade was the perfect embodiment of the festivals' ability to cast politics aside.
He said: "There is a larger turnout of Chinese paraders this year, but we also have a contingent from (Buddhist organisation] Falun Dafa, which has carried out protests outside the Chinese consulate for some years but have continually walked side by side with Chinese paraders.
"When the Festival was set up in 1947 it was with the aim of casting war and politics aside in the name of drama and the arts, and this is still as true today as it was then."
In keeping with the Oriental feel, the parade also includes a display of Japanese Samurai swordsmen.
David added: "The Cavalcade was started over 30 years ago by the EIF but it's grown to become a showcase for the Fringe, the Mela, the Jazz Festival and the Tattoo.
"It's a tough job bringing all of these people together. I've been doing the organising almost single-handedly, up until the day that is, since 2004 and it's a massive administrative task.
"It's a fun day, though, so it will all be worth it."
Fears were raised that the cavalcade may have been derailed by tram works this year, but the six-week hiatus afforded to the city centre during Festival time means the show will go on.
A police spokesman said: "We expect in the region of 175,000 people to attend this year's Cavalcade, and we have the appropriate number of officers in place to ensure the safety of the public and participants."
The grand parade starts at 2.30pm from Waverley Bridge, ending at 4.30pm at Johnston Terrace.
East Market Street, Cranston Street, Jeffrey Street, Market Street and Cockburn Street will be closed from 7am while the preparations get under way.
Then, from 10am, Princes Street will be closed eastbound from South Charlotte Street to Waverley Bridge. Closures will also take effect on Frederick Street, South St David Street from Rose Street to Princes Street, Meuse Lane and Johnston Terrace.
Princes Street will be closed completely from 11.30am and most of the city centre will be closed to all traffic from 1pm onward.
Free event organisers look to cash in on problems
PROMOTERS of free events are expecting the biggest audiences ever this year as locals and tourists feel the effect of the credit crunch.
Hundreds of free comedy, theatre, music, dance and children's shows are on offer throughout August, running alongside the thousands of paid events that make up Edinburgh's festivals.
With Fringe-goers feeling the pinch, combined with the problems the Fringe has had with printing and dispatching tickets, promoters of the free events believe their way is the best way to guarantee people see "good quality productions" this year.
Official Fringe figures show that there are 350 free shows and events this year – including Fringe Sunday and the Edinburgh Festivals' Cavalcade – which is up 15 per cent from last year.
The unofficial figure is likely to be around 400 as many of the free events were not listed in time to be included in the Fringe programme.
For the first time ever, there is also a free book festival, the West Port Book Festival, where literary events will be held in 11 venues, including in the area's several bookshops, the Meadows and the Edinburgh College of Art.
Alex Petty, Free Festival organiser, says 2008 will pull the biggest crowds into the free events that the Festival has ever seen.
The promoter, whose Laughing Horse Comedy company is putting on 158 shows, hopes the increase in people will also help dispel the myth that if they're free, they're no good.
He said: "We started five years ago and have grown each year from just two initially.
"Every year it's getting more and more accepted as a way of doing the Fringe, but there are still a lot of people who think 'it's free, it must be rubbish'.
"We have a good feeling that this year, with the credit crunch and problems getting Fringe tickets, we will see an increase in audiences."
THE PICK OF THE BARGAINS
• Fringe Sunday, Meadows, August 10
Jay Gees Jamboree, His Snurglegurk and Other Stuff, Edinburgh City Football Club, August 18-25
West Port Book Festival, August 14-17
Mr Mojo, Mum and Me, The Counting House, August 4
Rebecca Fawcett Art Display, Edinburgh City Football Club, August 1-25
Laughing Horse Free Pick of The Fringe, Espionage, August 1-25
Mario the Magnificent Flying Marionette, Art's Complex, August 4-13 (not 6 and 11)