Hello @Florina,

Let me help share other ways you can create a custom field to enter additional information needed on your transaction.

To start with, the express pick template has the same template used when creating a sales order. With this, here's how you can create the custom field in question:

1. Go to Customers.
2. Select Customer Center.
3. Find and open the profile of any of your customers.
4. Click Additional info.
5. Under CUSTOM FIELDS, select Define Fields.
6. Enter the name of your new custom field. Say Customer PO.
7. Put a checkmark under the Cust, Trans, and List columns.
8. Select OK.
9. Click OK.

Once done, let's go ahead and turn on the custom field to the sales order template you wanted to use. To do so:

1. Go to Lists.
2. Select Templates.
3. Find and open the information of the sales order template you wanted to use.
4. Click Additional Customization.
5. Put a checkmark under the Screen and Print columns.
6. Select OK.
7. Click OK.

Additionally, I've also included this reference for a compilation of articles you can use while working with us: The different ways you can track customer transactions in QuickBooks Desktop

If you have any other questions, please let me know by leaving any comments below. I'll be here to lend a helping hand.