Have you had a look at Chapter 9 of the included help?
Using commands to automate Monarch through the use of batch files is explained there.
If you have a programming background you might also consider using VB programs. There is a programmer's guide which can be downloaded from the Datawatch Web site.
In some ways how you approach the need will depend on what you want the task to do. Is it something that can be set up to run at a specific time or times during the day or does it need an 'on event' activation - for example a file appearing at a specific location?
If it is the latter, or you have large volumes of incoming files to process and distribute the results at random times during the day, you may need to consider a fully programmed solution to 'watch' a folder and take action when a report appears.
Alternatively, if volumes are high and the requirement is critical to work flow, look at upgrading to Monarch Datapump which adds input monitoring and processing, together with output distribution, to the core Monarch functionality to provide a comprehensive answer to such requirements without the need to create and maintain any additional code.
I hope these suggestions give you a starting point. There are a number of regular contributors here who do far more with scripting and programmed integration than I do and I am sure they will be along soon to add their advice.