To record a deal as converted (Paid out/delivered), you simply change the status of an application to a converted status, that will bring up a conversion box for you where you can choose an approval or add a conversion directly, by default if there is an approval we will take the data from the assigned approval and populate all the information for you.
You will notice there are two dates payout date and delivery date, these are really important as they are what will be used in reporting.