Hi there, Howard.

In QuickBooks Online (QBO), once you successfully create the template, you can make it as default. I can provide you with the steps to make your template as default.

Here's how:

1. Go to the + New icon, and click Invoices.
2. On the invoice, select Manage.
3. Select Design. Then, under Other templates, click Manage.
4. On the Custom form styles, under the Action column. Click the dropdown arrow and click Make default for both sales receipts and invoices.

If you have the old invoice layout, you can refer to these steps on how to:

1. Go to the + New icon. Then, select Invoices.
2. On the bottom part of the invoice, click Customize.
3. To make it default, choose the template you've created.

I've also added a couple of screenshots for your visual reference.

Furthermore, you can refer to our article on how to set a schedule for your invoices and send it to your customers: Create recurring transactions in QuickBooks Online

Don't hesitate to comment if you still have concerns about managing your invoices. I'm always here to help you.