Wordpress templates, or themes, are installed and enabled from the WordPress dashboard by clicking on Appearance, and then on Themes. From this page, you can install themes from a local hard drive or from the official theme directory. The theme directory sorts all themes based on their looks and functionality, allowing you to find a theme without knowing its name. Themes change the look and functionality of a blog, primarily by modifying design elements, like font and title settings.
To find a theme in the theme directory, either search by the name of the theme, or use the Feature Filter. The Feature Filter lets you search for themes based on their colors, layout, features and style. After searching, a list of themes is shown with a small preview of each one, as well as the option to either install the theme or show a larger preview..
WordPress also allows you to upload themes directly from your hard drive or other storage medium. To upload a theme, click on Upload at the top of the Install Themes page. Click Choose File, select the theme's archive, and press Install Now. Once it's installed, either press Activate, or return to the Themes page.