How to create a bootable USB stick on Mac OS X

1. 1

   Download Ubuntu Desktop

2. 2

   Open the Terminal (in /Applications/Utilities/ or query Terminal in Spotlight).

3. 3

   Convert the .iso file to .img using the convert option of hdiutil (e.g.,hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso)

   Note: OS X tends to put the .dmg ending on the output file automatically.

4. 4

   Run diskutil list to get the current list of devices.

5. 5

   Insert your flash media.

6. 6

   Run diskutil list again and determine the device node assigned to your flash media (e.g. /dev/disk2).

7. 7

   Run diskutil unmountDisk /dev/diskN (replace N with the disk number from the last command; in the previous example, N would be 2).

8. 8

   Execute sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m (replace /path/to/downloaded.img with the path where the image file is located; for example, ./ubuntu.imgor ./ubuntu.dmg).

   • Using /dev/rdisk instead of /dev/disk may be faster
   • If you see the error dd: Invalid number '1m', you are using GNU dd. Use the same command but replace bs=1m with bs=1M
   • If you see the error dd: /dev/diskN: Resource busy, make sure the disk is not in use. Start the 'Disk Utility.app' and unmount (don't eject) the drive
9. 9

   Run diskutil eject /dev/diskN and remove your flash media when the command completes.

10. 10

    Restart your Mac and press alt/option key while the Mac is restarting to choose the USB stick.

    
    

    
    

    From: http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-mac-osx