You can either install the Update via Windows Update, use Media Creation Tool or download Windows 10 with Anniversary Update ISO and then perform clean install.
Windows 10 Update Assistant
Along with these methods there are is a new way to get Anniversary Update for Windows 10. Windows has released Windows 10 Update Assistant utility to help users easily get the Anniversary Update. The Windows 10 Update Assistant tool downloads Anniversary Update and starts the installation of the update.
Using Windows 10 Update Assistant to upgrade to Windows 10 Anniversary Update
This is how you can download and install Anniversary Update.
Step 1: Head over to this Windows 10 update history page and click Get the Anniversary Update now button to download Windows10Upgrade28084.exe file.
If the above link doesn’t work then visit the link below and then click “Update now” button to download Windows10Upgrade9252.exe file.
Step 2: Run the downloaded Windows10Upgrade28084.exe or Windows10Upgrade9252.exe file to launch Windows 10 Update Assistant program. When you see the Update to the latest version of Windows 10 screen, click Update Now button.
Step 3: Once your click Update Now button, the Windows 10 Update Assistant will begin checking for any compatibility issues. If your PC is compatible and there is enough space to download and install the Anniversary Update, you will see OK button next to these requirements.
Step 4: Windows 10 Update Assistant will begin downloading Anniversary Update. The Anniversary Update download size is about 3 GB.
Step 5: Once downloaded, you will see Your update is ready. Your PC needs to restart to complete the update screen.
Click Restart now button to restart your PC and install the update.