Need Authorization Text and Signature Line To Only Show Up On Submission

I am doing a website for a doctor and we are using gravity forms to have people fill out their "New Patient" forms online before they come in for their first visit.

The only problem is that they need to sign these forms when they come in to the office for their first visit.

How do I do it so that they don't see the signature line when they fill out the forms online, but when the doctor prints out the forms the signature line prints out at the bottom for the patient to sign when they come in to the office?

Thanks

Yes he goes into Gravity Forms "Entries" in the WordPress Dashboard and then selects the entry and then selects Print on the bottom right side.

Can I add text in there also? So it would have the standard "Authorization" text and then under that a signature and date line for the patient to sign when they come into the office?

Example:

I Authorize this company to blah blah blah......, and certify that all of the above is accurate and true blah blah blah......
_______________________________________ __________________________
Signature Date