The Auto Assign function in Autoflow will automatically assign a Service Advisor or Technician to a active service visit  if no other user is currently assigned. 
To setup Auto Assign in your shop navigate to the Auto Assign & Update sub-menu under AI Setup. 
Then simply toggle on or off the actions that will cause the visit to Auto Assign to the user. 
Note: Auto Assign will not change the assignment of a visit that has already been assigned to a Service Advisor or Technician if a different Service Advisor or Technician completes an action that would normally assign the visit to a user.