To do this task
Open the type of form you want to customize.
For example, to open the invoice form click the Home icon and in the Customers section click Invoices.
Click the Customize drop-down arrow at the top of the form, then click Additional Customization.
Note: If you don't see the Customize drop-down arrow, you may need to resize or maximize the window.
If you see a "Locked Template" message for editing preprinted forms, either click Cancel to select another template, or click Make a Copy. Be sure to rename the copy.