The guide explains the process of USB Mapping on Windows using a tool called USBToolBox, crucial for building a Hackintosh. USB Mapping helps the system recognize the USB ports and manage their power, improving the overall stability. Steps include booting up Windows, downloading the USBToolBox, discovering USB ports, disabling the unused ones, and defining port types manually as needed. Finally, a personalized Kext is generated and placed in the specified directory followed by the OC Clean Snapshot.