|I would recommend buying a SOHO Router if the modem is not in fact a combination modem/router/wireless access point.|
As to the setup procedure, the installer should get it all setup for you. Typically, their job isn't done until you have a working connection.
If the installer left you with a highspeed internet connection that isn't working, call the provider and complain.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.