We pay out every month on the 1st of the month, just like you would receive a salary.
You can only be paid out if the Course you sold has been completed, i.e. if there are no outstanding Sessions for that Course, and you must also hit the "request payment" button on your Financial Transactions overview page for that Course to be included in your next payment.
This last part is for you to aggregate your incoming payments in order to reduce the bank charges incurred from receiving your payments. Banks charge money for every transfer. All bank charges for our outgoing payments must be borne by the receiver, you. The fewer transfers you have, the lower your overal bank charge will be, and the more money you keep.