It is strongly recommended that you install and activate the Easy Theme Options plugin as it is the key to configuring the theme without messing around with the theme code. You have to install the plugin yourself but it is in the WordPress Plugins Directory so you can use the Plugins menu and locate and install it without going through a download and upload process.
The plugin has to be configured by editing a file in the plugin's source directory, which isn't really ideal as it means it is likely it would need to be edited again if the plugin were to be updated. The instructions below show you how to edit the file so that it loads the code it requires from a file in the theme's directory. This means if the theme is updated you don't have to worry about reconfiguring the plugin.
Choose the Plugins entry in the WordPress admin menu and then select Editor and choose Easy Theme Options from the drop down list and hit Select. Then choose to edit the easy-theme-options/includes/options.php file. After the first line add:
if ( !include get_template_directory() . '/eto-options.php' ) :
The top of the file should now be similar to the following:
Before the last line add:
The bottom of the file should now read:
What that does is look for a file in the template directory, and only if it isn't found is the original content of the file read. The original content of the file isn't actually useful to the theme, of course, but it does preserve some useful sample code in the development environment and it seemed better to give instructions to do it the same way.
Once you have installed and configured Easy Theme Options you should go to the Theme Options entry under Appearance in the WordPress admin menu and you can make any changes you want to. As soon as you click on the Save Options button the Easy Theme Options will start overriding the options in the theme template files.
From version 3.4.2 there is a link to Theme Options in the WordPress Toolbar when you are viewing your site. It is in the drop down that has an icon alongside your site name.