try not to use unebootin, a lot of people get eror with unebootin. if you have bt4 beta installer, here is the easy way. it's my way installing usb live.
Originally Posted by Ro0t_
In bt4 beta
Format the usb with minimal 4gig become 1500MB vfat, and the rest using ext3 format. you can look "how to format" with googling. make first 1500MB bootable (using fdisk when you format the usb, code : a )
after that make format so your usb can be read.
after that mount the usb, then:
mkfs.vfat -F32 -n <name you want> /dev/<your first partition 1500MB>
mkfs.ext3 -b 4096 -L casper-rw /dev/<your second partition on usb>
after all the data copied,
rsync -avh <bt4prefinal data> <your target usb first partition 1500MB>
after that run nano or kate or something else you like, read the /mnt/<your usb first partition 1500MB>/boot/grub/menu.lst
grub-install --no-floppy --root-directory=/mnt/<your usb first partition 1500MB example sdb1 sdc1 sda1> /dev/<your usb example sdb sdc sda>
change default 0 to default 4 and look at start persistent Live cd, append vga=0x317 at the and on line that starting with kernel.
It will look like this:
save and boot with that usb, there is your usb live persistent.
title Start Persistent Live CD
kernel /boot/vmlinuz BOOT=casper boot=casper persistent rw quiet vga=0x317