1. Use the Add Check Mark tool under Fill & Sign tab. 1) In Foxit Reader/PhantomPDF V10 and greator, go to Fill & Sign tab, choose Add Check Mark Tool. 2)Click on the desired location where you want to add the check mark to create a check mark there. 3)Click on Hand tool or press ESC to exit editing mode. 2. Use the Windings 2 Font Linguistically a check mark is simply any mark with which one has checked items. Various possible check marks include "x-es" and "tick marks", as well as a host of other small marks used by proof readers, editors, accountants (auditing firms require a multi-page glossary of all the various check marks used for their audit trails !), etc.