It's easy to create a new invoice, placidus-tally.
There are different ways to create an invoice in QuickBooks Online.
We can select the Save and new if you're still in the invoice page. You can locate this button at the bottom right corner next to Save. This option will allow to create a new invoice within the invoice page.

Another way is to click on the Plus (+) icon. From there, select Invoice.

There is also an option to create an invoice if you're in the customer's profile. Under New transaction drop-down, let's select Invoice.

You'll want to read this article about recording a customer payment for your guide.
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