Read folktales written by prominent Africa writers such as Chinua Achebe, Buchi Emecheta and Dambudzo Marechera. These classic works will give you a feel for the art form and an insight into how African folktales are constructed.
Interview Africans and ask them to tell you some folktales. Notice how they structure the story and how they act it out. African folktales are often a theater production as well as a story.
Narrow your focus or create an anthology of folktales from different parts of Africa. Remember there are 53 countries, so you may want to concentrate on the folktales from one area, rather than spreading your stories too thinly.
Pick your characters. The financial independence of Yoruba women, for instance, is very different from that of the Berber. Make sure you identify the tribe the characters come from and describe the cultural and physical characteristics of your characters, as the Fulani look very different than the Ibo.
Develop a story line. Folktales were often set in villages, as that is where people lived, so you may want to go with a rural setting. Follow the folktale pattern of having a beginning, a middle and an ending.
Write your African folktale as if you were talking. Record your story and play it back to yourself to check it for tone. If you can't say a whole sentence without taking a breath, it is too long so shorten it.
Include magic or the supernatural. No matter if it is about the "ju-ju" men performing magic in a Nigerian folktale or the "jins" finding a crack and invading the human world and creating chaos, if it is an African folktale it has to include these elements.
Have a moral of the folktale. Stories were used to educate children and instruct them how to behave according to the tribal customs. Like Aesop's fables, there is a lesson to be learned from the folktale.