Applying for a visa can be administratively daunting, especially of it's your first time.
When make an application for a US Visa there are few things you need to keep in mind as well.
South Africans applying for a US visa can do so at any of the three U.S. Consulates in Johannesburg, Cape Town, and Durban.
The earlier the better
Don't waste time starting the application process. Earlier this month the consulate had a notice on it's website that encouraged South Africans seeking to apply for visa's to do so timeously. The statement reads: "the U.S. Mission aims to keep the wait time for appointments at a minimum. However, heavy demand for U.S. visas has currently led to a longer than usual wait time in South Africa."