To manually configure the Tecno T520, navigate to the settings menu and select "Network" to set up your mobile data and Wi-Fi connections.

For APN settings, go to "Mobile Networks," then "Access Point Names," and input the necessary details provided by your carrier. Adjust additional settings like display, sound, and kilascerita.com notifications according to your preferences. Lastly, ensure software updates are checked to keep the device running smoothly.