To avoid the anarchy of the period of the warring states, Qin Shi Huang and his prime minister Li Si completely abolished feudalism. What they did was divide the empire into 36 provinces each headed by three governors, one civil, one military, and one last to mediate between these two. Each of them was appointed by the emperor and could be dismissed by him. The civil governor was reassigned to a new province every few years to prevent him from accumulating a power base.
Qin Shi Huang ordered all former members of the royal houses of the conquered states to move to Xiangyang, the capital of Qin, in what is now the province of Shaanxi, to be kept under close surveillance, and prevent rebellious activities .
The emperor also developed an extensive network of roads and canals connecting the provinces to accelerate trade between them and to accelerate military movements to the provinces that opposed resistance.
Qin Shi Huang and Li Si unified China economically through the standardization of weights and measures, the currency, the length of the axles of the cars (such that any car could move without problems through the routes of the new roads), the legal system, etc. But perhaps most important of all, was that Chinese writing was unified.