Navigate to the Apps section of your Shopify store and select Amazon MCF by WebBee. Navigate to the Configuration Page > Marketplace Settings > Show Additional Settings (including Inventory Sync Settings).

If you want to send a Shopify order note (the one you or your customer entered during order creation) to your Amazon FBA/MCF warehouse, print it on the Amazon packing slip comment. To set the default packing label message, select Yes from the drop-down menu, then save your changes. If you want to print the same message on all of your Amazon packing slip comments.

Click "Add Label".

Enter the default packing label message. Hit the "Submit" and "Save" buttons.