Installing Windows 7 From USB Drive Without Any Software...

         I wanted to install windows 7 on my machine but without any software. So after searching a lot I got simple steps with out less prerequisites to install windows 7. Simply follow the steps given below.

Prerequisite : 

1. You need USB drive with at least 8GB of space.
2. Windows 7 bootable image.

Open Command Prompt :

Open command prompt from one the way's given below :

1. Open command from Start->All Programs->Accessories->Command Prompt.

2. Open run and type "cmd" and press Enter key.

open command prompt with "Run As Administrator", otherwise you won't get access.

Open Diskpart Utility:

on cmd type diskpart and press ENTER diskpart window will be open now.

Prepare USB Drive.

On the Diskpart window type "list disk".

All disk connected to computer will be listed. Select the one which is your USB Drive  by using below command.
select disk 1
Note : You can identify your Disk by observing the disk space.

Execute below commands.

CLEAN
CREATE PARTITION PRIMARY
SELECT PARTITION 1
ACTIVE
FORMAT FS=NTFS
ASSIGN
EXIT

Now if You have ISO image extract it with Winrar or any other software

Copy Installation Files:

Copy extracted files directly to USB Drive 
Note : don't create any folder inside USB Drive copy files as it is.
If you have DVD of windows 7 setup then also you can copy files from there to your USB Drive.