Wireless Router
Modern wireless routers often have a USB jack. Plug your printer into your router's USB port and install the driver to all computers utilizing it. A small utility program for network configuration will need to be installed.
Print Server
Connect the USB cable from the printer to a print server and it will communicate with an existing router. During setup, connect the print server to the router with an Ethernet cable and install the print server software following the installation wizard to configure the network settings.
Sharing
You can share a printer installed to one computer in much the same way as sharing files. Click "Start," "Control Panel" and type "network" in the search box. Click "Network and Sharing Center," then in the left pane click "Change Advanced Sharing Settings." Click the drop-down menu to expand the current network profile to be certain sharing is on. Click "Start," "Devices and Printers," then right-click on the Epson and click "Printer Properties," click the "Sharing" tab and click "Share." Others on the network will need to add it.