You generally need a "Metal-compatible" graphics card. AMD RX series cards (like the RX 580) work natively, while newer Nvidia cards (RTX/GTX 10xx and up) lack drivers for Mojave.
Follow the prompts. The system will restart several times; ensure you keep the USB plugged in until the setup is complete. A Note on Legalities and Security
It is the final version of macOS to support 32-bit applications. If you rely on older software or legacy plugins, Mojave is your last stop.
Do you have a specific you're planning to use for this build?
Mojave remains a "sweet spot" in the Hackintosh community for several reasons:
A wide array of "Kexts" (kernel extensions) for audio, Ethernet, and Wi-Fi are included in the installer to save you from manual post-installation hunting.

