diff --git a/docs/configuring-playbook-jitsi.md b/docs/configuring-playbook-jitsi.md
index f163976d..c2834244 100644
--- a/docs/configuring-playbook-jitsi.md
+++ b/docs/configuring-playbook-jitsi.md
@@ -25,8 +25,42 @@ Add this to your `inventory/host_vars/matrix.DOMAIN/vars.yml` configuration:
 matrix_jitsi_enabled: true
 ```
 
+## (Optional) configure internal Jitsi authentication and guests mode
+
+By default the Jitsi Meet instance does not require any kind of login and is open to use for anyone without registration.
+
+If you're fine with such an open Jitsi instance, please skip to [Apply changes](#apply-changes).
+
+If you would like to control who is allowed to open meetings on your new Jitsi instance, then please follow this step to enable Jitsi's `internal` authentication and guests mode. With this optional configuration, all meeting rooms have to be opened by at least one registered user, after that guests are free to join. If a registered host is not present yet, guests are put on hold into a waiting room.
+
+Add these two lines to your `inventory/host_vars/matrix.DOMAIN/vars.yml` configuration:
+
+```yaml
+matrix_jitsi_enable_auth: true
+matrix_jitsi_enable_guests: true
+```
+
+## Apply changes
+
 Then re-run the playbook: `ansible-playbook -i inventory/hosts setup.yml --tags=setup-all,start`
 
+## Required if configuring Jitsi with its internal authentication: register new users
+
+Until this gets integrated into the playbook, we need to register new users / meeting hosts for Jitsi manually.
+Please SSH into your matrix host machine and execute the following command targeting the `matrix-jitsi-prosody` container:
+
+```bash
+docker exec matrix-jitsi-prosody prosodyctl --config /config/prosody.cfg.lua register <USERNAME> matrix-jitsi-web <PASSWORD>
+```
+
+Run this command for each user you would like to create, replacing `<USERNAME>` and `<PASSWORD>` accordingly. After you've finished, please exit the host.
+
+**If you get an error** like this: "Error: Account creation/modification not supported.", it's likely that you had previously installed Jitsi without auth/guest support. The playbook can't yet rebuild all configuration files for some Jitsi services (like `matrix-jitsi-prosody`), which may cause such an error. **If you encounter this error**, we encourage you to:
+- stop all Jitsi services (`systemctl stop matrix-jitsi-*`)
+- remove the Jitsi Prosody configuration & data (`rm -rf /matrix/jitsi/prosody`)
+- rebuild Jitsi configuration and restart services (`ansible-playbook -i inventory/hosts setup.yml --tags=setup-jitsi,start`)
+- try the previously-failing command once again
+
 
 ## Usage