Read Instructions Carefully
Control your monitor brightness of your desktop computer by pressing F1 (decreasing brightness) or F2 (increasing brightness) keys.
How to install:
1) copy hackintoshBrightness.app to your application folder
2) Run hackintoshBrightness.app from your application folder and give it access from accessibility (located in System Preferences -> Security & Privacy -> Accessibility)
3) Add hackintoshBrightness.app on login items (located in System Preferences -> Users & Groups -> Login items)
4) Restart your hackintosh
Hackintosh Brightness Control works only on monitors connected with hdmi/dvi cables and only with few AMD/NVIDIA gpus.