On the left side of the Admin Dashboard, click the Enrollment tab, select your center, and drag the student from applied to accepted.

Scroll down on the student's application and click Add item

Here, you have the option to check the Charge immediately box. If this box is checked, the payment method below will be charged the amount listed. If it is a recurring charge, only the first installment will be charged immediately. All immediate charges on this form must have the same payment method.