The best way for anyone to travel is to make sure they plan the trip out ahead of time. You will find the trip to be safer, easier and you will surely enjoy it more.
First, get all of the tedious but important stuff out of the way. Check to ensure that your passport is not about to be expired. See whether or not you will need a visa. Organize some travelers checks in advance and consider travel and / or medical insurance if you like.
Double check your travel arrangement details and make sure not to forget to confirm your flights. (This includes connecting flights and return flights. Put in an order for any special meal on flights if necessary.
Given the moderate climate in South Africa, you will be comfortable during summer months in light summer clothes for the most part, but you should definitely pack a jacket, plenty of socks, a good pair of shoes and also a rain jacket just in case. Remember to pack sunscreen. Lots of sunscreen as well as sunglasses, a hat and some beach attire. To protect yourself from the sun make sure you have at least one cotton shirt with a collar. You should probably stock up on insect repellent. If you are planning to be in an area known for malaria, plan to wear long your sleeve shirt and some long pants in the evening. Also, make sure you bring good walking shoes.
If you are planning to visit in the winter, you should pack warm clothing. This should include a fleece because it can get very nippy in morning and night there. South Africans do not generally use the central heating so the cold takes many visitors by surprise.
Pack a cotton scarf or bandanna and a versatile wrap. If you will be watching game, aim for some reasonably neutral colors. Pack something that is warm for game drives. Something such as a windbreaker or a hoodie is an ideal choice. South Africans are pretty casual but you will need something more formal to change into if you are planning to visit exclusive hotels or other high end establishments.
If you take any pharmaceutical drug or medication, you should bring them along with an actual spare prescription. Custom regulations will allow you to bring in one month’s supply with you for your own personal use. It is a good idea to bring a letter from your doctor which confirms your medication.
Make sure you take two copies of all of your important documents. These include but are not limited to: your passports, itinerary and any emergency contact information as well. It is important to think of any additional information that may be needed as well.