This is what I used to flash via USB (I don't have a DVD drive)
Download the ISO from Crucial
Then get this tool
http://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/
Step 1 Scroll down to the bottom. Select 'Try Unlisted Linux ISO (New Syslinux)'
Step 2 Extract the Crucial ISO file from the zip file, point the program at the ISO file
Step 3 Select the USB drive letter.
Reboot and boot from the USB stick
Create
I found I had to format my usb stick to FAT32 beforehand, but other than that, this worked perfect