Just go to the Order. Use the "X Cancel" function (accessed via the three dots on the right). This will Cancel and Refund in full (from your Payment Account funds). If there are not enough available funds, Etsy may take the remainder from your Credit Card, But you will be reimbursed in full for all fees once the Cancellation completes. If you have no other orders, the payment for this Order may not be available for deposit until tomorrow, so it may not be available for the full amount of the refund, but you can either delay the cancellation until you do have sufficient funds available or you can cancel and refund and have the charges made to your CC. You can then use the funds from the Order (when available) to pay off the CC charge.
This is one of the good things about Etsy. Unlike Pay Pal and some other sites, Etsy does refund in full, including Payment Processing fees.
