You do not say where you are from but this might help.
Who requires a visa?
Nationals of the following countries may not require visas for stays of up to 90 days:
Argentina, Australia, Austria, Ballwick of Guernsey, Belgium, Brazil, British Virgin Islands, Canada, Chile, Denmark, Ecuador, Finland, France, Germany, Greece, N. Ireland, Israel, Italy, Jamaica, Japan, Liechtenstein, Luxemburg, Malta, Isle of Mann, Netherlands, New Zealand, Norway, Paraguay, Portugal, Spain, St Helena, Sweden, Swaziland, Switzerland, United Kingdom, United States of America, Uruguay and Venezuela.
It is highly recommended to contact the nearest Consulate for specific information on visa requirements that may be applicable to you.
What documents will be required?
A Confirmation of Acceptance by the educational institution concerned, as well as details regarding accommodation arrangements.
Proof of financial self-support
A return ticket
A doctor's medical statement
Medical health insurance
A letter of motivation setting out reasons why study at a South African educational institution is desired.
For work permits:
Official letter of employment from South African company stating salary and position.
For business visas:
Letter from employer.
Note:
In the case of failure to comply with any of these regulations, visitors may be required to leave a cash deposit with the Immigration Officer