You connect one end of the console cable to the router, and other end to the serial interface of your PC. Once that is done, you can start your terminal emulation program (Hyper Terminal comes by default with Windows). You will have to maintain the default settings, and once you get to the screen, press enter few times. You should get to the router command prompt.
Telnet does require a vty password to be set. This is a safety measure from Cisco. If you don't set a password, then anyone can telnet to the router and change the configuration. For setting vty password on the router, you will need to type following commands:
Router# conf t
Router(config)# line vty 0 4
Router(config-line)# password <password>
For getting dial-in access to the router, you will need to connect a modem to the AUX port of the router using Cisco AUX cable. Then you will need to connect a telephone line to this modem. Once this is done, you can use any utility like Hyper Terminal to dial the number of the phone line and get console access to the router remotely.
This was first published in November 2004