I've got you covered, boyd2828.
Mixing personal and business funds isn't advisable. Though, you may encounter situations that'll require you to do so. I'd suggest following these steps to record the funds accurately.
- Go to the Company menu and then select Make General Journal Entries.
- Pick the appropriate expense account in the first Account column.
- In the Debit column, type in the amount of the transaction.
- You can select the customer from the Name drop-down menu.
- Choose Owner’s Equity or Owner Investment in the second Account column.
- Click on Save and Close.

For more details about the process, please see this article: Create a Journal Entry in QuickBooks Desktop.
I'd also recommend consulting with an accountant for proper guidance. In case you don't have any, you can visit our Find an Accountant website to find one.
Additionally, I'm adding these articles that'll help you learn more about accounts receivable and payable workflow in QuickBooks Desktop.
Feel free to comment down below if you have any other concerns or questions about recording QuickBooks transactions. I'm always glad to help in any way I can.