The po is generated. Create the purchase order.If there is a purchase requisition, use it as a reference ( in Purchasing : Purchase order Create) A purchase order has three main areas, the header, item overview, and item detail. Each one has a small button that allows you to expand or hide it. You must call purchasing and have them make the changes in the PO since the order is already processed. Slippery Rock University – SAP Purchasing Instructions. In this video I would like to show you on how to create a fixed asset using a purchase order.