To accept payments via credit cards you will need to have a merchant account. Merchant accounts allow you to process and collect funds for customers that are paying via credit card.
To process credit cards in real time you will need to setup and configure an internet processing gateway for your merchant account. When you have the gateway setup, transactions will be submitted to your gateway before orders are accepted to authorize the customer's credit card. To complete the order and have funds transferred to your bank account, login and click the complete order button to close out the transaction and collect the funds.
Contact your merchant account provider to learn more about getting a payment gateway (virtual terminal) for credit card processing.
If you would like to apply for a merchant account, click the "store" tab and then click the "accept credit cards on your site" link