You can create a Runtime configuration from within the Project, and you can also link an existing Runtime configuration from another Project to your Project. See
Linking components into a Project for information on how to link a Runtime configuration to your Project, and
Structuring Projects using Global, Sub, and Main Projects for information on when to do so.
The name of the Runtime configuration should follow the naming standard used in your organization, for example include the document type (invoice, order, etc.) handled by the Runtime configuration.
The physical layers are created in the Platform, and inherited by the Runtime configuration. If, for example, the Platform contains a Development and Test layer, the Runtime configuration will also contain a Development and Test layer.
Now you have an empty Runtime configuration. To complete the Runtime configuration, you must add the appropriate Message configurations, connect the Message configurations to the connectors, etc. See
Runtime configuration procedures for information on how to configure a Runtime configuration.