When creating an invoice, you can select what payment method(s) you want to accept from your customer to get paid under the "Invoice details" section.
If you have a Merchant Account, you can currently accept card payments and/or bank transfers.
If you do not have a Merchant Account, you can accept bank transfers. To take card payments, you will need to apply for a Merchant Account.
Once your invoice has been created and sent, your customer will receive an email with a link to a hosted payment page. On this page, your customer will be able to view the payment method(s) you have selected for the invoice, and make the payment accordingly.