With WinMetro you will be able to try the Metro desktop without updating your Windows. It works in the exact same way as the original, running from the start and in the background to integrate with your system.
You can access the desktop by clicking the program´s icon in the toolbar or in the inferior left corner, like in Windows 8. If you bring the mouse nearer to the right side of the screen in the traditional desktop, the lateral bar will also appear and you will be able to access it through there.
Once in WinMetro, we will be able to see relevant information like the calendar, the weather, the stock-market and shortcuts to our photos, Facebook and Twitter or Skydrive. A list with our most used programs will appear to the right.
The application can be configured to open by default when Windows starts, and this way it will be more similar to Windows 8.
This is the best way to have this function without needing to update or a possibility for the hesitant is to try the Metro desktop before taking the leap.