This is quick tutorial to install a theme on windows 10. I’m so sorry, I don’t have to much time to make long-descripted tutorial. I hope you understand my bad English and sorry for the mess up grammar. Only work for Windows 10 build 10240 and lower (not compatible for build 10586 and higher).

Required Tools (link download on the end of the post) :
1. UxStyle for Windows 10
2. OldNewExplorer
3. Astyles 8.1 Theme Patcher
4. StartIsBack

Step : (Note : Always Make A System Restore Point. See How?)
1. Install UxStyle for Windows 10.
2. Install OldNewExplorer to show the Details Pane and remove the Ribbon. Configure the setting of OldNewExplorer just like the picture under this step.
3. Install Astyles Theme Patcher, this tool was used to remove the status bar and show the background folder. Look the picture under this step. Just select the option like the picture.

4. Install StartIsBack that compatible with Windows 10 to show the Start Menu.
5. Finish

(UPDATE 5 March 2016)
For Windows 10 Build 10568, check this video out :

and for Background Folder, try to use Astyles Patcher like before, tick the Patch Windows Background Folder.