Thanks for your interest in using QuickBooks Online Payments, derekj.

I'd be glad to walk you through the steps adding the Pay Now button on your invoice. You'll have to sign up for QuickBooks Payments.

Here's how:

1.  Click on the Settings icon.
2.  Choose Account and Settings.
3.  In the Payments section, click on Learn more.
4.  Complete the company information.
5.  You'll then be routed to this QuickBooks Payments page. From there, click on Add QuickBooks Payment. 

Please note that the application will take 2-3 business days. You'll be notified via email once it's approved. 

Now, you can start sending invoices with the Pay Now button and your customer can easily pay them directly online.

You can learn additional information on signing up for QuickBooks Payments in this article.

Please tag me directly in the comment below if you need anything else.