Sure, I'd be glad to help you prepare for your trip to Mbombela, Giyani, Addo, and Cape Town. Here are some useful travel tips:

Best Time to Visit:
The best time to travel in these parts of South Africa is between September and April when it's the warmest.

Route and Accessibility:
Cape Town, Mbombela, and Addo are easily accessible by flights. Giyani can be accessed by road or flights. You can plan a circuitous route like starting from Cape Town then heading to Giyani, proceed to Mbombela, and finally wrapping up your journey in Addo.

Altitude and Acclimatization:
Most parts of these cities lie at lower altitudes, so acclimatization will not be a concern.

Accommodation and Booking:
Accommodation ranges from luxury hotels, lodges to budget guesthouses and backpacker hostels. It is highly recommended to book your accommodations in advance, particularly during peak seasons.

Clothing and Essentials:
Pack summer clothes if you're traveling between September and April. Sunblock, sunglasses, and hats are essential to protect from the sun. But as the weather can be unpredictable, do not forget a good jacket or windbreaker for cooler evenings and possible rain showers.

Health and Safety:
Carry any prescribed personal medications. Stay hydrated and stay safe during outdoor activities. Follow the safety rules, particularly when interacting with wildlife in Addo Elephant National Park.

Local Etiquette and Respect:
South Africans appreciate politeness. So try and learn a few basic greetings in local dialects, respect local customs and traditions. In Cape Town, it is common to tip service providers such as taxi drivers, waiters, and tour guides.