Welcome to the TSO Translation Project maintained by Afr0 and the Project Dollhouse team. To contribute, make sure you have The Sims Online installed, then download Github for Windows, finally fork this repository.
You can find the files to translate in Maxis\The Sims Online\TSOClient\gamedata\uitext\english.dir. Make sure to look and see at the languages already provided by this project before starting your own. Once you've finished translating or fixing present translations, you can send us a pull request.
For languages with special characters such as æ, ø, å, or ä please make sure to save all your files as UTF-8, not ANSI, or they will break the client!