We use Crowdin for translating the Django Girls tutorial.
Go to our Crowdin page and have a look. If the language you want to translate the tutorial into is already listed, all you need to do is to create a free account on Crowdin and start contributing.
If the language you want to help with is missing, you can tell us so by:
writing to us at email@example.com or
creating a GitHub issue in the repository for our tutorial.
We will let you know as soon as we have added the language to our Crowdin page. Once that has happened, you can start translating, yay!