Before you file: check Help & how-to. Most "how do I" questions are answered there, including stocktakes, purchase orders and Xero matching.
Capture it while it's on screen — you won't need to describe it as carefully afterwards.
Pick the line that matches today. This is what sets the priority in the queue.
A copy is on its way to your inbox. Reply to that email any time to add detail — it lands straight on the ticket.