Add your Closing Stock to a Sales Order i.e. at the end of the season when you have completed all your deliveries but not force closed all Sales Orders and want to sell what you have left.
Closing Stock is not the same at Available to Sell - be sure that CLOSING is the stock you want to sell. For more information on adding Available To Sell stock to a Sales Order
You can manually change the quantity of products included on the Sales Order if you are not selling the full amount