I have used this links:
Making a pen drive bootable is possible in Windows7 & Windows8 operating system. Formatting a computer to install fresh Windows OS with a CD/DVD drive is not very good because it takes too much time to install fresh Windows operating system. There can also be a problem for many people that CD/DVD drive doesn’t work properly. So this can be a problem for them. Today laptop or desktop comes many USB ports. So there is no need of CD/DVD drive to format a system. Formatting is very fast and easy with flash drive/pen drive and also no software is required for this method. Windows7 or Windows8 command prompt can do the work with few lines of command. Just follow this tutorial.
Start your command prompt.
For windows7 users:
1. Go to “Start” button and click. Write “cmd” then cmd icon will appear on the top of the panel.
2. “Right click” on the cmd icon and click “Run as administrator”.
3. It will open the command prompt.
Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.
C:\Windows\system32>diskpart
Microsoft DiskPart version 6.1.7601
Copyright (C) 1999-2008 Microsoft Corporation.
On computer: SUMAN
DISKPART> list disk
Disk ### Status Size Free Dyn Gpt
-------- ------------- ------- ------- --- ---
Disk 0 Online 298 GB 1024 KB
Disk 1 Online 14 GB 0 B
DISKPART> select disk 1
Disk 1 is now the selected disk.
DISKPART> clean
DiskPart succeeded in cleaning the disk.
DISKPART> create partition primary
DiskPart succeeded in creating the specified partition.
DISKPART> list partition 1
The arguments specified for this command are not valid.
For more information on the command type: HELP LIST PARTITION
DISKPART> list partition
Partition ### Type Size Offset
------------- ---------------- ------- -------
* Partition 1 Primary 14 GB 1024 KB
DISKPART> select partition 1
Partition 1 is now the selected partition.
DISKPART> active
DiskPart marked the current partition as active.
DISKPART> format fs=ntfs
100 percent completed
DiskPart successfully formatted the volume.
DISKPART> active
DiskPart marked the current partition as active.
DISKPART> exit
Leaving DiskPart...
C:\Windows\system32>
