To access your Netopia router settings, open a web browser and type the default IP address, such as 192.168.1.1, into the address bar. You'll be prompted for a username and password; common defaults are 'admin' for both. Once logged in, navigate through the interface to configure your network, change Wi-Fi passwords, and set up security protocols. It's crucial to change the default credentials immediately to prevent unauthorized access. If you encounter issues, try resetting the router to factory settings. For detailed assistance, refer to the user manual or Netopia's support resources.