We do not enter serial numbers for inventory because we do a lot of on demand orders and shipping. However when processing an order we do need to enter the item serial numbers for those which have a serial, and enter the tracking information. 

I turned on the inventory module and advanced to add serial support but I cannot get my head around how to enter serials when processing the sales order when those serials not in inventory. Is there a custom button that we can use to automate adding them or something? Just looking for a process flow that works.