1. Open a PDF file you’d like to add a markup on.
2. Click on “Form & Sign” and select "Check Box" from the toolbar.
3. Click at the spot you’d like to put the check box. You can insert text into the type box.
4. If you’d like to confirm the function, please click the check box on the annotation bar again.
5. Click the annotation bar again to drag/edit the annotation.
Note: Please notice that the button tools are only for annotation purposes. The current version of PDF Reader has yet to support form-creating.