1. Visit Official Websites: Check reputable sites like 4U or 69Bits for official Windows downloads. These sites often cater to multiple platforms.

2. Select Correct Platform: Ensure you're downloading for your intended platform. For example, if you're on a PC, look for a "Windows" or "PC" download option.

3. Check for Restrictions: Review the game's terms of service to ensure you're downloading on a compatible version of Windows. Some games may only be available on specific OS versions.

4. Download Trial Version: If you prefer a free trial, look for a "Trial" or "Test" section on the download page.

5. Access Online: If online access is feasible, consider playing on a friend's PS4 or a remote computer. Check if the game allows online access.

6. Verify Game Availability: Ensure the game is available on your intended device. Some games support different platforms, such as Xbox or Nintendo Switch.

7. Install the Game: Once downloaded, install it on your PC. Follow on-screen instructions carefully to avoid errors.

8. Troubleshoot: If issues occur, check the game's terms of service or look for troubleshooting guides. If necessary, contact support or consider mods.

9. Backup Important Files: Save your important data before downloading to prevent loss.

By following these steps, you should be able to successfully download and enjoy Clash of Clans: Black Ops 3.