The most common task you usually face with after installation of some new theme on your website is the translation of the whole site and particularly your theme.
First of all, for sure, you should find translation package of default OpenCart template on your language. It can be find on the official website – http://www.opencart.com/index.php?route=extension/extension. Here you need to enter version of your default OpenCart and language. Download your package and upload all files to your site.
Only after all files are uploaded you can start to make settings in the admin panel.
As usual you can see settings directly in the extension page or in the documentation as for each language package. (see screen №1)
All these changes are to be done in the admin -> System -> Localization -> Languages. Click “Insert” button and write all parameters just as in the documentation (see screen № 2).
In the case you downloaded a language package with translation of front end and admin panel, you can set your own language in the admin panel. Do this in System -> Settings -> Local. Your required language can be selected from the dropdown list (see screen № 3).
All default texts are translated to this moment. But as for texts that are added by developers in a new theme additionally, they are not translated. So, you have to do this manually.
You should open folder: \catalog\language\english\ In your theme files. All files that you see there need to be copied in folder with other new language installed – \catalog\language\your_new_language\.
For example, for German:
You can translate all these files prior to uploading. Create the folder \catalog\language\de_DE, copy all files from \catalog\language\english\ there. After that translate them and upload to your site.
To translate language constants: open file, for example, \catalog\language\english\common\header.php. All constants you see in view of:
$_[‘text_home’] = ‘Home’;
Don’t touch left part of equal sign, you should change only words in right part of constants. So, you can change the word Home to your own translation.
Some themes, such as \catalog\language\english\common\header.php, \catalog\language\english\common\footer.php etc, do not change files from default OpenCart theme. They may contain only folder \catalog\language\english\module to translation. This makes your translation process easier and more quick.