In the case that you'd like to pay out or settle the balance of a single affiliate, you go to your Payments Page and click on the 'Settle Balance' located on the affiliate's row.
This will open a window showing the affiliate's outstanding balance and gives you the option to edit the amount. This is useful in the case that you'd like to create payout files for partial amounts.
If you'd like to process a payment up to a certain date, be sure to first use the "Up to" filter at the top of the table. Afterwards, you can proceed to settle the balance.
Note: Keep in mind that payouts are not automated. The file Tapfiliate generates can be used to carry out the payout in your preferred payment processing service (i.e. PayPal Payouts).