my son pays with cash how do I record

Thanks for dropping by, @MTV.

Let me guide you on how to record cash in QuickBooks Online. 

If your son pays you with cash, a sales receipt form is what you would use to capture the cash transaction in QBO. I’ll show you how:

1. Click the +New in the top left navigation bar. 
2. Under the Customers column, select Sales Receipt.
3. Enter/select the needed details on the field. 
4. Press Save.

Once you finish adding all details, you can click the Print or Preview option to display the PDF mode.

On the other hand, you can create a check or an expense if he’s part of the business. And he uses cash to pay his purchases or something. Here’s how you do it:

1. Select the +New button again.
2. Choose either Expense or Check under Vendors.
3. Enter the details.
4. Select Cash account under the Payment account. If you haven't set up this account yet, you can select + Add. Then, click this link for a detailed process: Add an account to your chart of accounts in QuickBooks Online.
5. Hit Save.

You might want to check these resources for extra information on how to record sales and expense transactions in QBO:

• Create and send a sales receipt
• Enter, edit, or delete expenses in QuickBooks Online

In case you need to create tailored content on your sales forms in the future, feel free to visit this article for reference: Customize invoices, estimates, and sales receipts.

Let me know if you need anything else. I'll be around to help you again.