Restore your SD Card (Mac)

Plug the SD Card into your MAC

Go to Spotlight (the little magnifying glass on the top right of your MAC), type Terminal, and press Enter

Now the rest of the commands are done in the Terminal

sudo bash and press enter

Type in your password to get the # prompt

cd /raspberry-pi/backups and press enter (or wherever you placed the backup img file)

df -h and look for your SD Card. My card is listed as /dev/disk1s1. Once you know which card is your SD Card type

diskutil unmount /dev/disk1s1 (or whatever your SD Card is listed as)

note:  I am not a Mac user but I note the commands below reference /dev/rdisk1 – I am not sure if that is the correct name for the SD card (it might be… but it seems a little odd based upon the instructions in the line above this)

dd bs=1m if=/raspberry-pi/backups/issbove.img of=/dev/rdisk1 and press enter

your SD Card will now be restore the backup

Once the backup is complete type:
diskutil eject /dev/rdisk1 (change rdisk1 to whatever is appropriate for your SD card)

This part of the instructions taken from this original article.