Yongnuo doesn’t currently have software available for easily updating firmware on their flashes, but this is how you can do it anyway.
Download the folder with all the files you’ll need here: https://goo.gl/yDiWCP
or download the firmware only from the Yongnuo website: http://www.hkyongnuo.com/e-detaily.php?ID=396
If you’re interested in the YN686EX-RT, check it out here:
YN686EX-RT (affiliate): http://prourls.co/903s
YN-E3-RT (affiliate): http://prourls.co/0Cx0
Want to see all the gear that I personally use and recommend? Click here:
Video “How To Update Yongnuo Firmware on a Mac” Author: Scott Dumas