Translation
Change the language of Miyus's interface text via Ghost's Publication Language setting — English included, German near-complete, more on request.
All of the theme's interface text — buttons, labels, form messages — is translated automatically based on the Publication Language set in Ghost Admin. Your post content is always whatever language you write in; this setting only affects the theme's own text.
Navigate to General settings within Ghost Admin.
Locate the Publication Language section.
Enter the appropriate language code (e.g., de for German) and save.

Included languages
Miyus currently ships with two languages:
en— English (complete; the default)de— German (near-complete; a couple of contact-form status messages currently fall back to English)
If a phrase has no translation in the selected language, the theme shows the English text for that phrase — nothing breaks, it just isn't translated.
Adding or extending a language
Each language lives as a simple file in the theme's locales/ folder (en.json, de.json, …) — a list of English phrases paired with their translations. To add a new language, the theme zip needs a new file like locales/fr.json with the same phrases translated; to extend one, the missing phrases are added to the existing file.
Free translation service
You don't have to do this yourself — we offer free translations for any language not listed above. Reach out to us with your language, and we'll add it to the theme for you.