What is the most important way for the people of South Sudan to make a living

Apart from exporting oil, they participate in agriculture.

Explanation:

South Sudan produces nearly three-fourths of the former Sudan's total oil output of nearly a half million barrels per day. The government derives almost 98% of its budget revenues from oil. Oil is exported through two pipelines that run to refineries and shipping facilities at Port Sudan on the Red Sea.

But despite the fact that they export oil, There are few large towns in southern Sudan and most people live in small villages in round, thatched houses. Most do not have electricity. People herd cattle at riverside camps in the dry season and grow millet and other grains in fixed settlements during the rainy season.

Southern Sudan country is located in northeastern Africa. Its rich biodiversity includes lush savannas, swamplands, and rainforests that are home to many species of wildlife, this helps them participate in vast agriculture.