As template please download the attached file "English.llg" and copy it anywhere. Later you can delete it.
1 Start Content tool and import language IDs
To create a new language, start the Content Tool and in the main menu choose "language files".
Now please import the downloaded language file. Therefore you can use the button "Add from another language (copy entries)" and afterwards choose the downloaded file in order to import it:
As you see, all IDs and English texts have been added.
Alternatively you can import the file without copying the texts. Of course this is not recommended. 
2 Appending finished translations
As soon as we append our German and English language file, you should append your translation file, as well. That works exactly as described above: Open your language file, click "append from file... (copy entries)", chose our new English language file from the OpenSource directory and scroll to the very bottom of the table. There you find all recently added language files, which have been added to the bottom of your language file. Our English translation is written to the right column, as usual. Now translate those texts, save, pack and upload it to the Workshop - done! 
Everyone who subscribed to your translation in the Workshop automatically receives your update.
3 General settings
Despite the translation the language ID needs to be set. This is the name of the language in the language, e.g. "English", "Deutsch", "Français".
Normally the font doesn't need to be changed. LOTUS is fully unicode compatible!
4 Translate
Now the big work begins. Every text in the right column needs to be translated.
Important: Sometimes the token %s appears. This is a placeholder and must not be removed. In addition, do not change the logical order of the tokens within a row.
As soon as the language file is saved and packed, LOTUS notices it within its properties. In addition, the container shows up in the workshop upload window and can be provided to others.
