Sign Document will operate in the same manner as Place Signature unless the document contains more than one unsigned digital signature field, in which case it will prompt the user to select the digital signature field they wish to sign Select Start. Choose the Add a Signature This document explains how to sign a document or agreement using Acrobat or Reader desktop application. To sign a PDF document or form, you can type, draw, or insert an image of your handwritten signature. Click on 'Upload'