How to make a Bootable Pendrive

How to make bootable usb stick in Windows 8 ::

Things you require-

1} Bootable windows xp,vista,7,8 DVD .

2} USB having free space as per the size of DVD you are using.
Steps>>

Goto run in the start menu type in it cmd.exe.Right click on it and select Run as Administrator.

Find the disk number of your USB Drive by typing the following into the Command Prompt window: diskpart

              list disk

When you write list disk you would get a list of disk drives or the usb drives that are online in your pc.*Be careful in next step only select the disk that is removable or you want to use.Format the drive by typing the next instructions into the same window. Replace the number “1” with the number of your disk below.(after every command press enter)

      select disk 1

      clean

      create partition primary

By writing so you made a partition which stores primary table.Follow these codes

      select partition 1

      active

      format fs=NTFS

You just selected the first primary partition and mad it active i.e., you are inside the table.

Now by entering fs=NTFS you are converting your usb type to NTFS and you are formatting it.

Wait until it gets to 100%
enter these code for finalising the usbstick to use.

      assign

      exit
When that is done you’ll have a formatted USB flash drive ready to be made bootable.

You just exit diskpart main menu.The formatted pen drive for loading boot manager is ready to use.Your next step is to load the boot manager into the pendrive.Insert your Windows 7/8 DVD into your drive.Change directory to the DVD’s boot directory where bootsect lies:

G: CD BOOT

CD BOOT

BOOTSECT.EXE /NT60 J:

*KEEP CAPS LOCK ON

In the above code G: is the drive conatining the bootable Windows7/ 8 DVD, and J: is the drive containing the removable usbstick.Exit cmd open up the usbstick. Copy paste all the files and folders from the DVD to the usbstick.Now you have a windows 8 bootable usbstick.
Aternatively:
You can also just copy and paste the files from your bootable DVD to pendrive. But sometimes you would fail in it as you need to have boot manager directly link when you are booting the drive.I also tried this to mount ISO files to usb in same way but then found it to be a crab, as ISO files dont have "bootsect.exe" <-- where the entire nutshell lies.