If you are 're storing data in cookies, you can use Cookie Value to pick up data when the form is submitted.
Select Cookie Value for Get Value From.
Enter the cookie Parameter Name you want and click Save.
You can enter a Default Value in case the parameter/cookie is not found.
If you want to capture data from the previous page the visitor came from before filling out the form, you can use Referrer Parameter.
Set Get Value From to Referrer Parameter.
Enter the Parameter Name which you want to snatch from the referrer URL and click Save.
You can enter a Default Value in case the referrer parameter is not found.
Click Approve and Close.
Sweet! You're doing pretty well. There's more to learn about Formsforms.