How to trigger a submit event for a future <form> element?

How to trigger a submit event for a future <form> element?

I am trying to hide confidential data being submitted by a payment button. Now I am wondering how I could catch the according <form> element being created "on the fly" and submit it automatically ensuring that there is no chance for anybody to access the data. I experimented with "live" but in my case nobody will "click" or "change" anything. Does anybody have a suggestion for me? Thank you!