In an African adventure a first aid kit has to be more advanced than a regular one:
Extra anti-malarial medication
antibiotics will help with stomach problems
a sterile syringe, sterile gloves and needle
A very common crime in this continent are the robberies because of the poverty, especially in the big cities:
so do not walk alone in a city at night
keep your money in a money belt or in a neck purse
hotels and accommodation facilities in Africa very rarely have locked doors, so keep valuables with you at any time, even when you sleep.
pay attention when you are traveling with public transport (keep your money in a pack wrapped around your leg or body)
Make sure that you have your travel insurance before you leave your country
Your luggage has to be very light. The distances in Africa are big and the clothes are cheap to buy.
In Africa the sun is strong and dangerous, so sun protection cream is absolutely necessary.
Remember to bring with you something to donate: medicals, clothes, money, even toys.
It is recommended to have binoculars and a decent camera with you, so you may re-live your experiences at home, but remember stay far away from the animals because is too dangerous and risky.