This is a quick guide that shows you how to change the parameters and set the level calibration values for your FY G4 gimbal.
You will need to use the FYtech USB dongle included with you G4 gimbal. But you will need to first install the windows drivers which can be downloaded here
You will also need to download the FY G4 gimbal setting software which you can find on the FY G4 downloads page
Can I use a Mac?
Unfortunately the FY G4 setting software and also the firmware update software only runs on PC right now, so if you need to do this you will need to use a windows PC. The other option is to use something like bootcamp on your mac.