There are two ways you can receive your commission: (1) through PayPal or (2) a check by postal mail.
If you choose to receive a check you should contact the seller directly to know you wish to use that option.
If you are on instant commissions you will be paid immediately at the time of sale if the transaction is processed through PayPal. Only transactions made by PayPal can be instant. Transactions made through the sellers credit card merchant account will be processed manually by the seller no sooner then 60 days from the date of the sale.