I just wanted to start out by saying that this is an abridged version of my original published version from April 27, 2022 that you can find on my website here.

Awhile back I realized I could combine different PDF files together using the built in Preview app that came on my Mac. I've since used this method when rearranging pages within a single PDF too!

To do this you first open the file(s) you want to adjust by selecting them, right-clicking on them, clicking Open with, and selecting Preview.

A different Preview window will open for each file and, by default for me, each will have their sidebar hidden. To move the pages around you will need that sidebar so go into View and select Thumbnails to show. Now you can see all the pages, in a thumbnail view, to the left of the current page.

Here you can click on any thumbnail and, while still clicking, drag it up or down to adjust the page ordering. If you want to combine two PDF files together you can drag the page(s) from its current window to where you want it in the new file.

This is also a simple way to duplicate pages too with the copy and paste function.

My file auto-saves when I close Preview so sometimes, if concerned, I copy the file, for a backup, before going through this process. That said, after saving and/or closing simply double-clicking on your file again will open it in your default PDF reader with all the page ordering changes made.

Hope you're having a wonderful day!

If you want the backstory and the full how to you can check out this original and longer published version from April 27, 2022 on my SimplyKyra website.