Dark mode and Dynamic desktop are among the best features of MacOS Mojave, though I freely acknowledge that, unlike Stacks or the new and improved Finder, they do nothing to make your Mac more powerful or easier to use. They're purely for show, but you're sure to find them the two most tangible and enjoyable new features of your Mac when you upgrade to Mojave this fall.
If you can't wait for the official release and don't want to, however, you can create your own version of Dynamic desktop right now on your current Mac. It's easy. Here's how.
DIY Dynamic desktop
introduces Dynamic desktop, a desert landscape wallpaper with shifting light. It features 16 images of the same sand dune scene but at different times of the day -- going from bright morning to warm afternoon to cool evening, with the shadows and clouds changing and the sky lightening and darkening as you go. Dynamic desktop changes from one image to the next throughout the day. It's a really fun feature.
To create your own Dynamic desktop, you can download a Zip file of the 16 images that Mojave uses and save them in a folder on your Mac. Mojave changes the image every 90 minutes to cycle through all 16 images every 24 hours. Because you can't set your Mac to change its wallpaper every hour and a half, you will need to duplicate half of the images so you end up with 24 files. This way, you can sync your DIY Dynamic desktop to the closest time interval MacOS offers, which is one hour. I just duplicated every other image so that I ended up with a balance of morning, afternoon and evening scenes.
With your folder of 24 Mojave images set, open System Preferences, click Desktop & Screen Saver and click the Desktop tab at the top. Next, drag your folder to the left-hand column under Folders. Check the box for Change picture and set it to Every hour.
Fun, 5-second preview
If you want to see a fun preview of your DIY Dynamic desktop, set the picture to change every 5 seconds in System Preferences, clear your desktop and sit back and enjoy the show.