How do I add a form to Facebook?

Do you want to embed the form to your Facebook page? If so, here's how: http://www.jotform.com/help/22-Adding-Form-to-Facebook

If you only want to share the form via Facebook, you can use your form URL https://www.jotform.com/help/401-Where-to-Find-My-Form-URL. You can also do that on the Publish page.