As an SA citizen you must contact the Swiss Consular in Cape Town and apply for the Family Reunification visa(D). This process may take up to 3 months, so I would start on the documents asap. More info here
http://www.eda.admin.ch/capetown
Consulate General of Switzerland
Embassy of Switzerland (Jan-Mar)
Nr.1 Thibault Square 26th Floor
(Cm. Long Str/Strijdom)
Cape Town 8001, South Africa
Postal address
Consulate General of Switzerland
P.O. Box 563
Cape Town 8000, South Africa
Tel.:+27 21400 75 00
+27 21 418 36 69 (Embassy Jan-Mar)
Fax:+27 21 418 36 88
+27 21 418 15 69 (Embassy Jan-Mar)
Office hours
(for all public and visas applicants)
Monday-Friday: 09:00-12:00
Saturday and Sunday closed