how to create a bootable usb hdd

I still amid of experiment but that how i do it along with ubuntu help most of the time I access help via https://help.ubuntu.com/9.04/installation-guide/i386/boot-usb-files.html how to get there is via Ubuntu Documentation > Ubuntu 9.04 > Ubuntu Installation Guide > Obtaining System Installation Media > Preparing Files for USB Memory Stick Booting I boot up using ubuntu live cd I used the partition editor (Gparted) to partition my 40 HDD 2.5" HDD to create the smallest partition 18mb FAT 16 the second partition is 10Gb EXT 3 / third partition 6Gb EXT 3 /home last partition 2Gb SWAP I committed the action Then I got problem continue so I continue to install the ubuntu on the ext hdd I have to install Gpart as not in std installation #apt-get install gpart but i take a rest next day I read the ubuntu help again and it is much clearer the first partition i created is /dev/sda1 download to /tmp fr netboot/boot.img.gz # zcat boot.img.gz > /dev/sda1 All the files are there ! [last night I struggle to copy the system file vmlinuz (kernel binary) initrd.gz (initial ramdisk image) but it is either not able to be copied in the installed sytem or I do not it is contained in the casper directory in the LiveCD ] then i #mount /dev/sdX1 /mnt try to use vi but forgot all command so i use the text editor and found the files in the /mnt directory change the file syslinux.cfg include menu.cfg default vesamenu.c32 prompt 0 timeout 0 to default vmlinuz append initrd=initrd.gz only ========================== THIS PORTION is found to be fatal and wrong after that root@ubuntu:/mnt# cd / root@ubuntu:/# umount /mnt root@ubuntu:/# root@ubuntu:/# install-mbr /dev/sda1 The program 'install-mbr' is currently not installed. You can install it by typing: apt-get install mbr -bash: install-mbr: command not found root@ubuntu:/# root@ubuntu:/# apt-get install mbr after installing ... mbr root@ubuntu:/# install-mbr /dev/sda1 THIS PORTION does not work for HDD and distroy all the works done as in the rest of section ================================================ let try and it should works I try on old PC and does not work but it does work well on HP nx6325 notebook