Use an Ethernet cable to connect from the network-port on your computer to one of the LAN ports on the router.
Click Start
Click Run
Type CMD
Press Enter
Type IPCONFIG
Press Enter
You should see output like:
IP Address. . . . . . . . . . . . : 192.168.1.100
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
if the router has self-configured, and is ready for "wired" usage.
Then, start Internet Explorer.
Type
http://192.168.1.1
Press Enter
Login to the web-server "inside" the router
Click to run the "Wireless Networking Setup Wizard" to configure it for "wireless" usage.