Even though the Egyptian revolution has frequently been described as leaderless and it clearly enjoyed support from all sections of Egyptian society and beyond being a demand for democratic rights was non-ideological, it was not unplanned.

An article in the Wall Street Journal and a documentary by Al Jazeera reveal new details of some of the ingenious and meticulous organization that translated the will of the Egyptian people into a viable force capable of toppling a regime.

The youth organizers of the uprising knew their challenge was to outwit police who were expert at containing demonstrations and keeping ordinary Egyptians away.

They met daily for two weeks [in early January] in the cramped living room of the mother of Ziad al-Alimi. Mr. Alimi is a leading youth organizer for Mr. ElBaradei’s campaign group. His mother, a former activist who served six months in prison for her role leading protests during the bread riots in 1977, lives in the middle-class neighborhood of Agouza on the west bank of the Nile.

Those present included representatives from six youth movements connected to opposition political parties, groups advocating labor rights and the Muslim Brotherhood.

They chose 20 protest sites, usually connected to mosques, in densely populated working-class neighborhoods around Cairo. They hoped that such a large number of scattered rallies would strain security forces, draw larger numbers and increase the likelihood that some protesters would be able to break out and link up in Tahrir Square.

The group publicly called for protests at those sites for Jan. 25, a national holiday celebrating the country’s widely reviled police force. They announced the sites of the demonstrations on the Internet and called for protests to begin at each one after prayers at about 2 p.m.

But that wasn’t all.

“The 21st site, no one knew about,” Mr. Kamel said.

To be sure, these activists weren’t the only ones calling for protests that day. Other influential groups rallied their resources to the cause. The Facebook page for Khaled Said, the young man beaten to death by police in Alexandria, had emerged months earlier as an online gathering place for activists in Egypt.

There was an Arabic page and an English page, and each had its own administrators. Mr. Ghonim, the Google executive, has now been identified as one. The pages’ other administrators remain anonymous.

An administrator for the English-language page, who uses the online moniker El-Shaheed, or The Martyr, recounted the administrators’ role in the protests in an interview with The Wall Street Journal via Gmail Chat. El-Shaheed recalled exchanging messages with the site’s Arabic-language administrator on Jan. 14, just as news broke of the Tunisian president’s flight from his country. Mr. Kamel and his cohorts, who had already begun plotting their protest, now had another powerful recruiting force.

“I was talking with Arabic admin and we were watching Tunisia and the moment we heard Ben Ali ran away, he said, ‘We have to do something,’ ” said El-Shaheed, whose true identity couldn’t be determined.

The Arabic administrator posted on the Arabic page an open question to readers: “What do you think we should give as a gift to the brutal Egyptian police on their day?”

“The answer came from everyone: Tunisia Tunisia : ),” wrote El-Shaheed.

For the final three days before the protest, Mr. Kamel and his fellow plotters say they slept away from home, fearing police would come to arrest them in the middle of the night. Worrying their cellphones would be monitored, they used those of family members or friends.

They sent small teams to do reconnaissance on the secret 21st site. It was the Bulaq al-Dakrour neighborhood’s Hayiss Sweet Shop, whose storefront and tiled sidewalk plaza—meant to accommodate outdoor tables in warmer months—would make an easy-to-find rallying point in an otherwise tangled neighborhood no different from countless others around the city.

The plotters say they knew that the demonstrations’ success would depend on the participation of ordinary Egyptians in working-class districts like this one, where the Internet and Facebook aren’t as widely used. They distributed fliers around the city in the days leading up to the demonstration, concentrating efforts on Bulaq al-Dakrour.

“It gave people the idea that a revolution would start on Jan. 25,” Mr. Kamel said.

In the days leading up to the demonstration, organizers sent small teams of plotters to walk the protest routes at various speeds, to synchronize how separate protests would link up.

On Jan. 25, security forces predictably deployed by the thousands at each of the announced demonstration sites. Meanwhile, four field commanders chosen from the organizers’ committee began dispatching activists in cells of 10. To boost secrecy, only one person per cell knew their destination.

In these small groups, the protesters advanced toward the Hayiss Sweet Shop, massing into a crowd of 300 demonstrators free from police control. The lack of security prompted neighborhood residents to stream by the hundreds out of the neighborhood’s cramped alleyways, swelling the crowd into the thousands, say sweet-shop employees who watched the scene unfold.

At 1:15 p.m., they began marching toward downtown Cairo. By the time police redeployed a small contingent to block their path, the protesters’ ranks had grown enough to easily overpower them.

The other marches organized at mosques around the city failed to reach Tahrir Square, their efforts foiled by riot-police cordons. The Bulaq al-Dakrour marchers, the only group to reach their objective, occupied Tahrir Square for several hours until after midnight, when police attacked demonstrators with tear gas and rubber bullets.

It was the first time Egyptians had seen such a demonstration in their streets, and it provided a spark credited with emboldening tens of thousands of people to come out to protest the following Friday. On Jan. 28, they seized Tahrir Square again. They have stayed there since.