Make some additions to Dimension documentation

docs/configuring-dns.md

@@ -41,7 +41,7 @@ As the table above illustrates, you need to create 2 subdomains (`matrix.<your-d
 The `riot.<your-domain>` subdomain is necessary, because this playbook installs the Riot web client for you.
 If you'd rather instruct the playbook not to install Riot (`matrix_riot_web_enabled: false` when [Configuring the playbook](configuring-playbook.md) later), feel free to skip the `riot.<your-domain>` DNS record.
 
-The `dimension.<your-domain>` subdomain is necessary, because this playbook installs the Dimension integrations manager for you. Dimension installation is disabled by default and if you explicitly do not enable it's installation (`matrix_dimension_enabled: true` when [Configuring the playbook](configuring-playbook.md) later), feel free to skip the `dimension.<your-domain>` DNS record.
+The `dimension.<your-domain>` subdomain may be necessary, because this playbook could install the [Dimension integrations manager](http://dimension.t2bot.io/) for you. Dimension installation is disabled by default, because it's only possible to install it after the other Matrix services are working (see [Setting up Dimension](docs/configuring-playbook-dimension.md) later). If you do not wish to set up Dimension, feel free to skip the `dimension.<your-domain>` DNS record.
 
 
 ## `_matrix._tcp` SRV record setup (temporary requirement)

docs/configuring-playbook-dimension.md

@@ -1,15 +1,20 @@
 # Setting up Dimension (optional)
 
-Dimension integrations manager installation is disabled by default. You can enable it in your configuration file (`inventory/matrix.<your-domain>/vars.yml`):
+**Dimension can only be installed after Matrix services are installed and running.**  
+If you're just installing Matrix services for the first time, please continue with the [Configuration](configuring-playbook.md) / [Installation](installing.md) flow and come back here later.
+
+## Prerequisites
+For an Integration Manager like Dimension to work, your server needs to have federation enabled (`matrix_synapse_federation_enabled: true`). This is the default for this playbook, so unless you've explicitly disabled federation, you're okay.
+
+Other important prerequisite is the `dimension.<your-domain>` DNS record being set up correctly. See [Configuring your DNS server](configuring-dns.md) on how to set up DNS record correctly.
+
+## Enable
+[Dimension integrations manager](https://dimension.t2bot.io) installation is disabled by default. You can enable it in your configuration file (`inventory/matrix.<your-domain>/vars.yml`):
 
 ```yaml
 matrix_dimension_enabled: true
 ```
-Your Matrix also needs federation enabled for Dimension to work, so if you have disabled it by setting `matrix_synapse_federation_enabled` to `false`, please remove or comment this variable in your configuration file. Or set it to:
 
-```yaml
-matrix_synapse_federation_enabled: true
-```
 
 ## Define admin users
 These users can modify the integrations this Dimension supports. Admin interface is accessible by opening Dimension in Riot and clicking the settings icon.  

docs/configuring-playbook.md

@@ -55,4 +55,4 @@ When you're done with all the configuration you'd like to do, continue with [Ins
 
 - [Setting up Appservice Discord bridging](configuring-playbook-bridge-appservice-discord.md) (optional)
 
-- [Setting up Dimension (optional)](configuring-playbook-dimension.md) (optional)
+- [Setting up Dimension](configuring-playbook-dimension.md) (optional)

docs/installing.md

@@ -36,5 +36,6 @@ Now that the services are running, you might want to:
 
 - **finalize the installation process** (required for federation to work!) by [Configuring Service Discovery via .well-known](configuring-well-known.md)
 - or [create your first user account](registering-users.md)
+- or [set up the Dimension Integrations Manager](configuring-playbook-dimension.md)
 - or [check if services work](maintenance-checking-services.md)
 - or learn how to [upgrade your services when new versions are released](maintenance-upgrading-services.md)