Lets begain the guide without wasting time.
Just make sure that your USB Flash/Pen drive is bootableand with capacity of more than 4GB.Requirements :
> Windows 7 ,or Windows Vista ,or Windows XP ‘s setup disk or ISO file.
> A Pen drive of 4 GB 2 GB sufficient for XP)
> 15 minuets of Free Time ….
>Insert Pen drive and make sure you’ve copied your data as it will get formatted in process.
>Now download WinToFlash from this link : http://wintoflash.com/download/en/ and open it,it looks like this
>Run tool and Select your Windows 7,Vista,XP Files (make sure that your usb drive letter is correct).
>Now select your parameters of your windows 7,Vista ,Xp setup.
>Select correct destination drive path and correct sourcr(disk setup) path.[you can use use virtual drives too if want to work with ISO setup image]
>Click on run after setting all correctly and Wait..
YOU ARE DONE…..
>Make sure that your pen drive is bootable,i’ve tested windows 7 setup on SanDisk pendrive of 8GB..
MoserBear’s pen drive are not bootable.
>make sure that your bios is computable with USB booting and booting with external drive is checked in.
you can change settings from boot screen while booting your computer…
>Still facing problem ,comment about it.