If a Registrant selects the pay later option during their purchase the Events Grid will show a Dollar Icon on left side of the row. This Dollar Icon means that there is money owed on that purchase. To add a Payment to that purchase click the Dollar Icon.

This will launch a dialog window where you can select which items you are including in the payment by setting the toggle to YES next to the ticket level or add-on. Once you have selected the items, the total will be displayed and you can enter the Payment Type, Check Number if applicable, and include a Memo if desired. Before selecting a payment type you have the option to enter in a Coupon Code to give the purchaser a discount on their Pay Later transaction.  

If payment will be made with a credit card, you can select a card on file, enter a new card and billing information, and choose whether or not to include the processing fees.