To set up your router for fiber internet quickly, connect the router to your fiber modem, access the router's settings via a web browser, and input the provided ISP credentials. Make sure to update the firmware, configure Wi-Fi security, and customize your network name for optimal performance. However, setting up a fiber optic connection to your router can seem daunting if you're unfamiliar with the process. Whether you are using a router provided by your Internet Service Provider (ISP) or have. Connect a Coax cable from the wall jack to the side of the Splitter (Coax In) with a single port.