How to sign a submitted document

Hi, I have a document that needs to be signed after form submission as the calculations need to be done. How can I do this please? 

I'm not sure what exactly to do, but you can edit your submission: https://www.jotform.com/help/325-How-to-Edit-Submissions-Made-on-Your-Forms

There you can view form with prefilled data and you can sign and submit.

Is that what you had in mind?

Thank you!