Mac OS X offers a great solution for this, as it has the option to automatically shuffle wallpapers in the set period of time.
Simply follow these instructions:
1.) Click on Apple menu (Apple icon in the top left corner of the screen).
2.) Select “System Preferences”.
3.) Choose “Desktop & Screen Saver”.
4.) Check the “Change picture” option and select the period of time in which the desktop wallpaper will be changed.
5.) Optionally, you can check the “Random order” box if you want to shuffle wallpapers in a random order.
6.) Once you’re done, exit the window and you’re set.
Mac101 