What is the best way to protect a page offering a free download after a viewer has filled out a form? I am using Contact Form 7 and Download Monitor on a Genesis theme. Some of the things that came to my mind are a session variable, referer or a hidden form field. We don't want the page to be accessed directly.
I am currently using Get variables and a hidden form field, but, the url with the variables could still be shared. It is a "free" download, so the goal is not iron clad security, but, just wasn't sure if other method might be better.