1. Make sure your screen resolution is 1920x1080.
2. Download Rainmeter and install it.
rainmeter.net/cms/3. Download the Assassin's Creed Rainmeter file. Double Click it to install it. Make sure the theme installs.
ionstorm01.deviantart.com/art/…4. Right click on any visible skin or find the Rainmeter icon in the task bar and left click "Manage Skin".
5. Click the "Layout" Tab. Make sure the AC skin is loaded. If not, load it.
6. The wallpaper is located in the @resources folder of the skin directory. Set it as your desktop wallpaper.
Hope that helps. Have Fun!