I don’t create bootable USB sticks that often but every time I do it I think that it’s harder than it really is and start to search the web for walkthroughs.
This post could also simply be written: Look at the Ubuntu download page.
Here is the process for OS X:
- Download ISO file of the operating system you want to put on the USB stick
- Open the terminal
- Convert the ISO file using the convert option of hdiutil: hdiutil convert -format UDRW -o /path/to/target.img /path/to/source.iso
- Run diskutil list to get the current list of devices
- Insert the USB stick
- Run diskutil list again to determine the device node assigned to your USB stick
- Unmount the USB stick: diskutil unmountDisk /dev/diskN
- Write the image to the USB stick: sudo dd if=/path/to/disk.img of=/dev/rdiskN bs=1m
- Eject the USB stick: diskutil eject /dev/diskN
