Simply enable the module. All ordinary tasks should be handled automatically.
CiviCRM Message Templates have both a *name* and an email *subject*, but Mosaico templates do not have a subject. By default the name of the Mosaico template will be used for both the message template name and also its subject. This might or might not be appropriate to your use case.
As a work-around, you can use the format `title | subject` to specify your Mosaico template name. e.g.
| Mosaico Template Title | Message Template Title | Email subject |