The "Assistant"-style concept of PDFStamp makes it very easy to use. Here's how it works in a nutshell:
1. Simply drag your documents (files or complete folders, it doesn't matter) over the drop target in the first pane of the main window.
2. In the second pane use any of the predefined stamps or define your own. You can have as many stamps per document as you want. You can also specify if the stamps are to be applied to all pages, a range of pages.
3. Set output options like target folder in the third pane. The final name is assembled from a basename (filename or a custom text), an optional counter, and an optional postfix.
4. Review your settings - you can anytime go back to a previous step.
5. For a test run with a single PDF, click the upper "Start" button in the fifth pane. PDFStamp will then process only the first of the source PDFs. If you are happy with the result, click the lower "Start" button to process the whole set of documents.
Please note: The software has been tested extensively with thousands of PDFs, many with more than a thousand pages. However, it's simply not possible to test against each PDF generator and variety. Should you find problems with one of your documents, please let us know.