The report you designed can range from a simple print template, to a detailed complicated form.
If the report replaces one of the existing stock templates, then you would need to select that from the Preferences of the application. For example, the below graphic brings up the preferences in the Invoices App. You can change the Print Template of the invoice to one you created in the report designer.
For example, if you created a custom Contact report, you may add a button to generate that report on the View Contacts. For more details on Customization, you can visit our customization section.