1. Connect the Nokia 5200 to a computer using the provided USB data cable.
2. Open the web browser on the computer and go to the Opera Mini website.
3. Click on the "Download" button and select the Nokia 5200 model from the list of available devices.
4. Once the download is complete, transfer the Opera Mini installation file to the phone's memory card using the USB cable.
5. Disconnect the phone from the computer and open the "File Manager" application on the phone.
6. Locate the Opera Mini installation file on the memory card and click on it to begin the installation process.
7. Follow the on-screen instructions to complete the installation.
8. Once the installation is complete, open the Opera Mini application and start browsing the internet.