From the QuickBooks support site.
"QuickBooks forms, such as invoices, sales receipts, and statements, use templates that can be customized with the Layout Designer to suit many needs.
Detailed Instructions
To customize a template:
Open the appropriate form. For example, to customize an invoice template, open the Create Invoices form.
Click the Template drop-down arrow and select the template to be customized.
Click the Customize button to open the Layout Designer.
Customize the template as needed. Use the Layout Designer Help feature for further assistance in using the Layout Designer.
Select the File menu and select Save As.
Enter a unique name for the new template in the Save As field (for example, My Company Invoice).
Click OK.
Select the Layout Designer menu and select Quit Layout Designer."
There are several custom areas here you can change. Look for a tab that allows you to check and uncheck boxes for items to display on screen or include on printed form.
This
link might help you understand a bit better. Its from the PC version.