Make use of the Checkbox style option available for YesNo fields.
To create a YesNo field and display it as a checkbox:
- Login as Admin and click on the Admin icon.
- Click on the Fields link.
- Click on the Add Field button.
- Select YesNo and click Continue.
- Enter a name for the field in "Label". Set the Display Style to "Checkbox" and set the other available options.
- Click OK to save the field.
- Click on the Manage Forms for this Field button to add the field to the desired form.
- Click on a form and click on the Add button.