If you'd like Processors to be automatically assigned to new orders/submissions in your instance based on certain criteria, login to the Admin page of your FastGem instance and click 'Config.' 

 

In the 'General Config' tab, scroll down until you find the 'Auto Assign Processor' section, toggle 'Enable Sub Auto Assign Processor' to 'Yes' and choose whether to auto-assign based on language or availability:

 

Don't forget to click 'Save' when you're done!