How do I change a PDF from portrait to landscape?

Great news, you can do that on this very page! 

Scroll up on the PDF rotator guide page to be able to do the following:

1. Upload your document in the PDF rotator box
2. Use the buttons at the bottom, next to the blue one — rotate left/right one time
3. Click “Apply Changes”

And that's it! You're done — your PDF has now gone from portrait to landscape!