Theme Installation Guide
Once you've found your theme, what do you do with it? Here's a short guide on how to install your new Drupal theme.
There are two types of themes in the Drupal world - complete/stand alone themes and sub-themes.
Complete Themes
Download and extract the archive to your sites/all/themes folder—then visit the themes list page to enable and configure your themes settings. Some themes have many advanced settings so its well worth investigating the theme settings page.
Sub-themes
Many of the themes on this site are "sub-themes". In Drupal-speak this means they require the "base theme" to be present in the themes folder in your site, or they won't work, and you'll probably get an error.
On each theme page you may see the icon with a link to download the base theme. Download and extract the base theme, then place it in your sites/all/themes folder on your live site. Normally you don't need to enable base themes but for some features to work this may be a requirement.