As a Publisher you receive OmniCoins for each new user listing that other users publish on your server. But, you must keep your server continuously running and connected to the Internet, so that those listings are available.
The ZIP files on this page install a database and web server on your computer. Install the software by running the "install" script located in the main folder. Please read the README.txt file for details.
You must open the following ports in order for the Publisher software to work:
80 (TCP) -- Web server
4984 (TCP) -- Sync_gateway
8090 (TCP) -- Blockchain
8500 (UDP) -- DHT.