How to make Bootable USB on OSX

A Bootable USB is very useful to install new Operating System. 

On OSX (in my case : 10.7.x Lion), make bootable USB stick.

i. prepare ISO file (Linux, FreeBSD, others) 
ii. using Discutil erase "freespace" on USB stick
iii. Open terminal
iv. check USB stick location
   $diskutil list /dev/disk1

/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 GB     disk1

v. change directory which located ISO files
    $cd ISO-files location
    ex.) $cd Downloads
vi. make img file from ISO
    hdiutil Usage :    hdiutil convert -format -o [options] 
    $hdiutil convert -format UDRW -o FreeBSD9 FreeBSD9.x.iso FreeBSD9
vii. writing using DD
   $dd if=./FreeBSD9.dmg of=/dev/rdisk1