When you’ve been sent an invoice, it will appear at the top of your Dashboard in a big blue box. Inside, you’ll see a button labelled “View Invoice”. Click on it! You can also click on the invoice due under "Activity" or "Transactions."
This will bring you to the Projects page where you can see the invoice due. Select Pay Now. From here, you can select the payment method you want to use and process the payment easily. No additional charges are added to the amount due.