He tells us that he worked as an ironer (mikwagi) and that he used to sing at parties in the street -- the traditional way that simsimiyya music, known as damma, was performed at the time. He says he was contacted by director Hossam el-Din Mustafa to appear in the film, which stars Farid Shawki, Mahmoud El-Meleigy, Nahed Sharif, and Nagwa Fouad. He says that he sings on two songs, but I can only find one. The song starts at about 31:45. Check it out.
When the group El Tanbura was formed in late 1988 under the leadership of Zakaria Ibrahim, el-Gizawy was one of the veteran artists recruited to join the project of reviving the Port Said musical tradition that seemed to be dying out. He appears as a singer on all four of the group's albums. Sayed Gizawy passed away in October 2015. Allah Yarhamu.