If your coach allows it, you're able to store one or more payment cards on file for the automatic payment of future invoices.

You'll find the place to view and manage these from your My Account >> My Invoicing >> Payments cards page, like so:

Click  +Payment Card to add a card to your account.

After entering your credit card details, you can tick the box at the bottom to enable automatic billing:

You can enable automatic billing, so that you don't have to manually pay your coach's invoice every time. Whenever your coach sends you an invoice, it will be paid automatically if you have turned on this switch: 

To remove your credit card for whatever reason, simply click the trash can icon over to the right. 

To replace the card, simply click on +Payment Card.