Mint install from usb

If you want to try MINT on your computer without modifying anything to the already installed system, you can use the Live CD/DVD images that Linux Mint uses to distribute its is version of Linux. Live_CD . As the inclusion of cd/dvd drives in lots of computers have been discontinued, eg netbooks etc It makes sense to use a flash/usb drive instead of the cd.
If you want to have certain features retained between reboots then you need to look at persistence.
This is what makes using a live image far more useful the most users, it allows you to keep your bookmarks and documents and to some degree install new programs that will be saved between boots. Persistence must be saved to a flash or hard drive so why not do away with the live cd and have have the USB load the iso image and automatically load the settings from the persistence file.
You'll need your live USB to install Mint on some of the other howto's on this site.
Form windows you need to download the ISO file of your choice form http://www.linuxmint.com/download.php
Then to write the iso to your flash drive download
From Linux Mint follow this supplement
1. http://unetbootin.sourceforge.net/
OR
2. http://www.pendrivelinux.com/yumi-multiboot-usb-creator/
For this tutorial we will use UNETBOOTIN

Plug in your usb remember to back up anything you need to keep. Find the USB drive and make a note of the drive letter.
Right click and and format the drive, are you sure you have the correct usb drive.
Are you ready to format drive - last chance - make sure its the right one.
Once the format is complete start Unetbootin, you will see there are several options; but it is quite simple to use.
1st Make sure you have the correct usb drive selected it will automatically try to select any plugged in usb/flash drives. 2nd Chose the iso use want to use – here we are using the smaller version (no codecs or libre office etc) of mint for this tutorial that you should have previously downloaded. 3rd Add persistence, remember 1000mb = 1 Gigabyte, the larger size of persistence file the longer it will take to make the file. You should make a minimum size of 1000 mb or larger for normal day to day use.   Obviously this depends on the size of flash stick you are using.   Once you are happy with your choices press OK to start the writing process.
Making the usb , copying the files from the iso to the usb.
Making the usb, making the required files and adding persistence this make take some time.
Ready to try
Mint 11 live desktop, here you can see that we are installing from this live usb to a harddisk.
This is a  LXDE edition of the Mint 12 Live desktop that uses the Lightweight X11 Desktop Environment (LXDE)
Mint 12 live desktop

After you have your livecd setup with new wallpapers, bookmarks and such its a good idea to back up the casper-rw file from your usb stick. If you keep this backup relatively up to date and you have problems booting from the stick, delete the casper-rw file and check weather the stick will boot, if it does copy the backup onto the stick and you have your system up and running in no time.     If you have to remake the Live USB just make a small persistence file then overwrite with the backup.

There is a good write up of persistence at what-is-persistent-linux