Copying an image to the SD card in Mac OS X

• Download the image
• Extract the image
• From the terminal run df -h
• Connect the SD card reader with the SD card inside
• Run df -h again and look for the new device that wasn’t listed last time. Record the device name of the filesystem’s partition, for example, /dev/disk1s1
• Unmount the partition so that you will be allowed to overwrite the disk
  sudo diskutil unmount /dev/disk1s1
• Using the device name of the partition work out the raw device name for the entire disk, by omitting the final “s1″ and replacing “disk” with “rdisk”.
  Exemple: /dev/disk1s1 -> /dev/rdisk1
• In the terminal write the image to the card with this command, using the raw disk device name from above
  sudo dd bs=1m if=~/Downloads/YourImageFolder/YourImage.img of=/dev/rdisk1
• If the above command report an error(dd: bs: illegal numeric value), please change bs=1M to bs=1m
• After the dd command finishes, eject the card
  sudo diskutil eject /dev/rdisk1
• Insert it in your device to boot from and have fun!

Follow the above steps if you think you are geeky, the easiest way on mac: http://alltheware.wordpress.com/2012/12/11/easiest-way-sd-card-setup/