How to install Debian from USB? (Using full size image not netinstall)

How about downloading the CD1 ISO, then put it on a USB and boot? (My favourite)

How about using an automated tool such as UNetbootin?

Here is another tool from Pendrivelinux.

As of Debian 6.0 (Squeeze), the netinstall and disc 1 of the regular install CD/DVDs are 'hybrid' ISOs. They can be burned to an optical disc and booted or copied onto a USB drive and booted.

To copy the ISO onto a USB drive from a linux system all you need to do is cat the ISO onto the drive.

cat debian.iso > /dev/sdX

http://www.debian.org/releases/squeeze/i386/ch04s03.html.en#usb-copy-isohybrid