To get the universal usb installer click on the link(Universal-USB-Installer-1.8.7.2) to download it.(size about 980kb)

To get the mint12 iso goto this download link (http://www.linuxmint.com/download.php ) and you will see a page like below —

   here you may choose the iso as per your requirement whether cd or dvd and which architecture depending on your system.Here i choose dvd 64-bit which is of 0.99gb in size and wait for the download to finish.

Now that you have both the tool and your pendrive(min. 2gb size) ready then double click on universal usb installer icon to open it…

You will get a window like this and choose the options as shown…

choose I Agree …

here you have to choose linux mint 12 dvd from the list in the drop down box of step 1 then give the path of your iso in step 2 then choose your drive letter of your pendrive and check the format checkbox to clear the contents of the pendrive before installing….finally choose create

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    Step 2 : iso image
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after clicking on create you will see something like this …
choose ‘yes’

creation process starts ….wait for few minutes!!

finally it shows Installation Done,Process is Complete!
click on close….yipee!!! your live usb is ready
now you can choose to boot from usb at the system start and see that your usb is up and running!!