To process your orders with pick list as your starting point, you will have to create batches of shipments compulsorily.
So basically you have to follow these steps:
Add shipments to a batch.
2. Create a pick list for a batch. For this you have to create a picklist manually and then apply filter for the given batch ID and add all the filtered products to a picklist.
3. Create the pick list for all the filtered shipments.
4. The Shipments’ status will be “To be picked”. You will Receive the Pick list from the same page. The Shipments’ status will be “Picked”.
5. On the Shipments page, filter out the batch number and process the shipments as you have always been doing!