NAME
dd -- convert and copy a file
SYNOPSIS
dd [operands ...]
DESCRIPTION
The dd utility copies the standard input to the standard output. Input
data is read and written in 512-byte blocks. If input reads are short,
input from multiple reads are aggregated to form the output block. When
finished, dd displays the number of complete and partial input and output
blocks and truncated input records to the standard error output.
Plug-in your USB stick and find what "/dev/diskN" it is mapped to by opening Terminal (where "N" stands for "disk0", "disk1", "disk2" etc). To do so, please execute:
# diskutil list
or
#df
Unmount USB Stick
Unmount the USB stick
# diskutil unmountDisk /dev/diskN
Where /dev/diskN is the one you have found in previous step as per our example it would be "/dev/disk2".
Write ISO to USB or
Write the content of the ISO file:
# sudo dd if=/path/to/downloaded.iso of=/dev/rdiskN bs=1m
/dev/rdiskN is the same disk you have found previously, with an r in front. r is for raw disk, as writing to /dev/rdisk2 is much faster than writing to /dev/disk2. You will be prompted for the administrator's password.