It is part of the campaign to raise Sh66 million for the construction of a pitch of international standards, to help local youths nurture their talents.
Nyamai who is the head of Rig East Africa, is partnering with Kibra MP Peter Orero to raise the funds for the project.
Orero said the hardship local footballers and children have been facing while training will be a thing of the past once the project is complete.
"This is one of the projects that we hope will develop and improve talents around this area," Orero said during the ground breaking ceremony on Thursday.
Architect Maithya Musunga said the pitch has been designed in such a way that it can be reconfigured to accommodate various activities.
"The main pitch will be an international standard soccer pitch," he said.
Nyamai said works involves construction of a football stadium facility complete with bleachers all round the pitch, teams' changing rooms for both boys and girls, ablution facilities for both girls and boys, stadium lighting, drainage facilities, anti-climb fencing around the pitch, complete marking of pitch to approval, pitch accessories including goal posts.
She has offered to walk a total of 488km from Mombasa to Nairobi in 14 days to raise funds and create awareness about the project.
"From December 1 to 15, I will be walking from Mombasa to Nairobi to create awareness and raise funds for this project which we are calling #488 for Kibra."
Nyamai said she plans to cover the total distance in 14 days, and will be undertaking 30km per day.
Nyamai said MP Orero has agreed to walk with her for the first 30km from Mombasa in support of the project. The flagging of the project will be held in Mombasa on Friday.
"We are hoping this is going to create awareness that the problem we see in our society, we do not have to wait a big donor from the West, to come do it. Ourselves as Kenyans can come together raise the money and do it," she said.
Nyamai said Kibra will no longer be the biggest slum in East Africa but the rising of Africa.
Rig East Africa is a christian organisation that focuses on community development.
School Principle Silas Opiyo said the schools population is 5,500 and coordination can present a huge challenge to the school.
Opiyo said bad injuries to students have given him more headaches due to the rocky surfaces hindering proper child development.
"Learning should be holistic,when the school has got a user friendly field, it will not only attract our children, but also help residents and by that we will be adding value,"Opiyo said.
He said the refurbishment of the playing ground will not only be a benefit to pupils but also the community. The project is said to be complete in January 2024 before schools reopen.
