This is a quick how to on backing up your Raspberry Pi SD Card
Shutdown the Raspberry Pi and remove the SD Card
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
Type:
sudo bash and press enter
Type in your password to get the # prompt
Type:
mkdir /raspberry-pi and press enter
mkdir /raspberry-pi/backups and press enter
cd /raspberry-pi/backups and press enter
Type
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)
dd if=/dev/rdisk1 of=/raspberry-pi/backups/wheezy-todaysdate-backup.img bs=1m and press enter
your SD Card will now be backed up
Once the backup is complete type:
diskutil eject /dev/rdisk1
And that is it.