Tweak user's guide

docs/user_guide.md

@@ -33,7 +33,9 @@ Whenever one of these config items is updated, an `Update` activity will be sent
 
 ### Customization
 
-TODO
+#### Custom emoji
+
+You can add custom emoji in the `data/custom_emoji` directory and they will be picked automatically.
 
 ## Public website
 
@@ -92,10 +94,6 @@ print("I will be highlighted")
 
 ~~~
 
-### Custom emoji
-
-TODO
-
 ## Interactions
 
 microblog.pub supports the most common interactions supported by the Fediverse.
@@ -136,9 +134,11 @@ TODO side-effect of receiving a webmention.
 
 All the data generated by the server is located in the `data/` directory:
 
- - The server configuration (in `profile.toml`)
- - The server secrets
- - The SQLite3 database
- - The uploaded media
+ - Configuration files
+ - Server secrets
+ - SQLite3 database
+ - Theme modifications
+ - Custom emoji
+ - Uploaded media
 
 Restoring is as easy as adding your backed up `data/` directory into a fresh deployment.