Since a Scenario is a series of Actions, organizing the actions that will initiate when the Scenario is launched is a key component of configuring any Scenario.
To edit a Scenario, go to Scenario Manager >> Scenarios and then Active (or Inactive, if your scenario is new and hasn't been activated yet.)
Then navigate to the Actions tab for the scenario.
You'll see a dropdown of Available actions. Select any of the actions that you'd like to attach to your scenario.