Save a Dynamically Created File on Server

I am writing an application to allow applicants to submit a completed application.  There are two files: one they will view (with more color and formatting efforts etc) and a plain one for print.  I want them to click on the Submit Final button in the pretty formatted one, and then I will upload the plain one on the server as the final submission.
Both will be dynamically created file pulling data from database at that moment.  How do I save a dynamically created file on server? 
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