In your Pragma installation directory you will find a "pragma_server.exe". This is the executable you need to start a dedicated server.
By default this will start the game, but not load a map right away. To change the map, you can either use the "map <map>" console command, or use the launch parameter by the same name.
If you want to automate the process and load a map immediately on startup, you can use the following batch-script:
start pragma_server.exe -log log.txt 2 -map <yourMap>
You can also add launch-commands to the "server.cfg" in the "cfg"-directory, which will be loaded automatically on startup. (This will not load by default when creating an ingame server, however.)
For people to be able to join from a different network, you will also have to forward the ports Pragma is using, and make sure to let it through the firewall.
By default Pragma uses the TCP/UDP port 29150. You can change these using the "-tcp" and "-udp" launch parameters.
Accessing server console
To run commands on the server you can simply use the console. If you need to run them remotely, you can run commands from your local game when connected to the server. To do this, simply add the "rcon" prefix to your commands (e.g. "rcon sv_cheats 1").
This requires that you have the same password specified with the "rcon_password" command as on the server.
Q: My server won't show up in the server browser / People can't connect to my server
A: Make sure you have your ports opened properly as described above. If you have a firewall, either disable it, or add an exception for Pragma.
Q: My server crashes on startup
A: Enable the log by adding "-log log.txt 2" to the launch parameters. Start the game until the crash occurs, then check the generated log-file for errors.