Click on the patient's 'Invoice tab'

Click on the invoice you would like to apply payment to

If processing payment by card or bank account click 'Process Payment'

If you want to only apply partial payment: in the box that pops up edit the text box with the full amount so the 'Process Payment' button reflects the amount you want to process. Select the payment source you would like to use and click 'Process Payment for $XXX'

Click the blue 'Record Payment' button

In the box that pops up, indicate how much of the full payment you would like to mark as received

Select the form of payment you have received and include a memo if you would like

Click 'Record $XXX Payment'