Stock can be allocated to a sales order individually or in bulk.
This is done from the stock reservation view, which can be accessed from a sales order via the Stock menu as shown:
Here you will be able to scan items in via serial number or barcode.
There are a few options here.
Auto-allocate to order
Auto-allocation will allocate all products available in stock on FIFO (First In First Out) basis.
This will remove all allocations for the order.
If your customer decides to make changes to the products in the sales order, you can remove all reservations and then remove items from the sales order. You can then replace them with new products.
Increase the quantity of items you can view on the page
If you have an order with many products you can increase the number of items viewed on one page.
Check available stock
On the left-side of the screen, you can see if there is any Available Stock already booked in.
You can arrange your products by the ones that have not been allocated yet by clicking on the Allocated header.