YEAR END PROCESSING WITH ENCUMBRANCE

We are having first time procure to pay year end with encumbrance. What steps should be consider during this process:

for example:

1. should we cancel all in-process PR

2. should we cancel all in-process PO

3. should we record receipt for approved PO or it can be left

4. can we left approved PR & PO without recording receipts

5. can we left un-invoiced receipts without recording invoices

please let me know all mandatory / optional steps in sequencial order.

Regards,