Paypal payments
On receipt of your invoice (on or before the due date), you should login to the billing system (WHMCS) and click to View the invoice you want to pay.
Once in the invoice, there is a link to make payment via subscription; then follow the instructions provided by Paypal.
NOTE: If you pay after the due date, the system will only allow you to pay that one invoice, and you will have to wait for the next invoice to be able to set up a subscription
Credit Cards
On receipt of your invoice (on or before the due date), you should login to the billing system (WHMCS) and click to View the invoice you want to pay.
When you have entered your credit card details and made a successful payment, your card details are stored and will be used for future invoices.
Debit Cards
It is not possible to set up a recurring payment on a debit card (this is a merchant restriction, not ours!)