First of all, you have to be the official translator !

If you're the one, you just have to :

1) Click on Manage my translations  in the Main Menu-> Web Translation  System on the left side, then pick the one you wish and click on its title, the list of all languages for the extension appears.

2) Click on the "long name" of your language and the page containing the list of locale files will open.

3) Edit one file with the appropriate button

4) Then fill the translation form for each string, just below the english version.                                                                                                                            

5) You can translate partially and not necessarily in the item order. You have NOT to bother about encoding problems, the WTS will manage with that !  (Once you have done with it, do not forget to click on "Save".)

             6) Do the same with every file of the list.

Note: you have to be logged in order to access to the Web Translation System

 

For more information, please see the other Questions & Answers