Theme selection is made in the Theme Preferences dialog box. This dialog box is opened via the Theme icon in the Settings dialog box.
Before You Begin
22 About GNOME Personal Settings
28 About Desktop Themes
Open Theme Preferences Dialog
From the Settings dialog box, double-click the Theme icon. This opens the Theme Preferences dialog box.
Select a New Theme
In the Theme Preferences dialog box select a new theme from the theme list. The changes that the theme makes to the window controls and borders are applied to your currently open windows (including the Theme Preferences dialog box). You can then close the Theme Preferences dialog box; select Close.