This theme is localisation ready, which means you can use localisation tools to translate your theme. Please use one of the below tools to translate your theme. I personally prefer Poedit.
Pootle: An open source web-based translation system. The server hosted at Locamotion.org currently has WordPress translation enabled on it.
Poedit: An open source program for Windows, Mac OS X and UNIX/Linux which provides an easy-to-use GUI for editing PO files and generate MO files.
GNU Gettext: The official Gettext tools package contains command-line tools for creating POTs, manipulating POs, and generating MOs. “For those comfortable with a command shell“
The translation file is located in languages folder (/inc/languages). Edit the .po file using POEdit, use the translation field to make replacements.
From the file menu, save file with your language name e.g de_DE.po. It will generate both a .po and .mo file for your translation.
Next edit wp-config.php located in the root folder of wordpress and define the WPLANG prefix with your language name which should be similar to the translation file name.
You can find more info on editing the wp-config.php and adding the WPLANG prefix here: http://codex.wordpress.org/Editing_wp-config.php#Language_and_Language_Directory