diff --git a/support/documentation/content/contributing/document/_index.en.md b/support/documentation/content/contributing/document/_index.en.md
index 6ab42044..0e1b07fe 100644
--- a/support/documentation/content/contributing/document/_index.en.md
+++ b/support/documentation/content/contributing/document/_index.en.md
@@ -34,6 +34,16 @@ Please note that a missing translation file will not appear in the menus of the
 
 For this, there is a script `doc-generate-missing-translations.sh` in the root of the repository. When you add a new file, you just have to create the english version, then run this script. It will create all  missing translations, putting a sample message inviting the user to read the english version.
 
+## Add a new language
+
+In the `support/documentation/config.toml` file, please copy and modify the `[Languages.fr]` section.
+
+Then, run the `doc-generate-missing-translations.sh` script.
+It will create all the missing files.
+
+Then you can translate them one by one.
+If the translations are not complete, it does not matter, the generated files will display a message suggesting to change the language.
+
 ## Preview
 
 To preview your modifications, just run:
diff --git a/support/documentation/content/contributing/document/_index.fr.md b/support/documentation/content/contributing/document/_index.fr.md
index b1d19991..51152989 100644
--- a/support/documentation/content/contributing/document/_index.fr.md
+++ b/support/documentation/content/contributing/document/_index.fr.md
@@ -45,6 +45,18 @@ anglaise, puis de lancer ce script. Il va créer toutes les traductions
 manquantes, on y mettant un message type invitant l'utilisateur⋅rice à lire la
 version anglaise.
 
+## Ajout d'une nouvelle langue
+
+Dans le fichier `support/documentation/config.toml`, inspirez vous de la
+section `[Languages.fr]` pour déclarer la nouvelle langue.
+
+Ensuite, lancez le script `doc-generate-missing-translations.sh` à la racine
+du dépot. Celui-ci crééra tous les fichiers manquants pour la nouvelle langue.
+
+Il ne vous reste plus qu'à les traduire.
+Si les traductions ne sont pas complètes, ce n'est pas grave, les fichiers
+générés afficherons un message proposant de changer de langue.
+
 ## Prévisualiser
 
 Pour prévisualiser vos modification, il suffit de lancer: