Set the license key in your server.cfg using sv_licenseKey "licenseKeyGoesHere".
Start the server from the server-data folder. For example, in a plain Windows command prompt (cmd.exe) window:cd /d D:\FXServer\server-data D:\FXServer\server\FXServer.exe +exec server.cfg (the /d flag is only needed when changing directory to somewhere on a different drive)
Create a new folder (for example mkdir /home/username/FXServer/server), this will be used for the server binaries.
Download the latest master branch build for Linux from the artifacts server(copy the URL for the latest server version and use wget <url> to download it).
Extract the build to the directory that was previously created, using cd /home/username/FXServer/server && tar xf fx.tar.xz (you need to have xz installed, on Debian/Ubuntu this is in the xz-utils package).
Clone cfx-server-data in a new folder outside of your server binaries folder. 4b. For example git clone https://github.com/citizenfx/cfx-server-data.git /home/username/FXServer/server-data
Make a server.cfg file in your server-data folder (copy the example server.cfg file below into that file).