Select the PDF document you want to fill in and sign. Add an electronic signature to a PDF document online in a few easy steps Click Fill & Sign on the left-hand side or click E-Sign at the top. This, Type your name, sign with the computer’s mouse, or upload an image of your signature. This document explains how to sign a document or agreement using Acrobat or Reader desktop application. The name you type here will also be the name it uses in any name fields on the form To sign a PDF document o