To hook up a Wi-Fi router, connect it to your modem via Ethernet cable, and plug the router into an electrical outlet. Allow the router to run for at least one minute before double-clicking the network notification in the taskbar on the computer. Select the router to connect to it.
Setup a network username and password to keep your wireless network private. Most Wi-Fi routers simply need to be hooked up to begin working, but if it does not, unhook it from the modem and electrical outlet. Locate the setup disc that came with the router, and place it in the CD drive of the computer. Be ready to connect the router to the modem and power source, and follow the onscreen instructions to complete setup.
If you are unable to get the router working with its included setup software, reconnect it to your modem and power source, but also connect it to your computer with an Ethernet cable. Find the default IP address, username and password assigned to your modem in the instruction manual. Open your preferred Web browser and type the IP address in the address bar. Use "http://192.168.1.1", "http://192.168.0.1" or "http://192.168.2.1" if you cannot find yours.
After you type your IP address into the address bar, enter the default username and password. Create a new username and password, and disconnect the Ethernet cable connecting the router to the computer to connect wirelessly.