On her completion of Matric in 1972, Nombuso did casual work such as typing documents for the Garment Workers union, while she looked for permanent work. Her exposure to union documents resulted in her familiarity with the Labour Law and the conditions that were facing workers in their various workplaces. After her stint with the Garment workers union, Nombuso moved to become the general secretary of the Chemical and Industrial Workers’ Union, during her time with the union, she was visited, on numerous occasions by the special security branch for questioning.
In 1979 she resigned from her work in the union and in 1980 she went to work for an Adult Basic Education project as a trainer, where she trained Basic Education trainers. In 1982, she once again moved to work as a paralegal practitioner for the Legal Resources Centre, where she interviewed clients for the attorneys working in the center. Her work in the Legal Resources center once again involved her working closely with trade unionists, however she became frustrated when she could not herself represent people, even though she had experience both in labour law and the functioning of trade unions. In 1993, Nombuso thus went to the University of Natal where she enrolled for a BProc. Degree that allowed her to have a formal legal background that she had lacked while working as a paralegal. She completed her studies in 1995 and in the following year she resumed work as a lecturer at the Mangosuthu Technikon in Umlazi township. Her lectureship at the technikon lasted a year, after which she went to work for the South African Clothing and Textile Union (SACTU), where she is currently working.