Adding Printer To Network

I've connected two computers together before but now, I having a problem, 3 of my computers are connected via a DSL router and sharing internet access, but I want to also share a printer, and the computers are connected to the network automatically, with no IP address or I don't see the IP address, computer says connected automatically. How do I share my printer?

Please.

Get on the computer connected to the printer. Then go to control panel, then click printers and faxes, and find the printer you want to share, right click it, from the drop down list click sharing click the option share this printer and than ok.