You can create a Windows bootable USB flash drive to install windows operating system in your PC . As we know that USB Flash Drive are much faster than a ordinary CD/DVD RW optical drive, so the performance is much better when we install Operating System using USB flash Drive.
Basically mostly Windows Operating System can be fit in a 4 GB USB, but some updated Windows Operating System take much memory, so i recommend you to use 8 GB USB.
Let’s create a bootable USB flash drive.
Step 1: Insert a USB flash drive into a running computer.
Step 2: Open a Command Prompt window as an administrator.
Step 3: Type
Step 4: In the new command line window that opens, to determine the USB flash drive number or drive letter, at the command prompt, type
list disk and then click ENTER. The list disk command displays all the disks on the computer. Note the drive number or drive letter of the USB flash drive.
Step 5: At the command prompt, type
select disk 1 click ENTER.
Note: Drive number can be change if you have inserted more than than 1 USB drive or PC have more than 1 Hard Drive.
Step 6: Type
cleanand the click ENTER. This command deletes all data from the USB flash drive.
Step 7: To create a new primary partition on the USB flash drive, type
create partition primary and then click ENTER.
Step 8: To select the partition that you just created, type
select partition 1 and then click ENTER.
Step 9: To activate the partition type
active then click ENTER.
Step 10: To format the partition, type
format fs=ntfs quick and then click ENTER.
Note: If your PC supports Unified Extensible Firmware Interface (UEFI), you should format the USB flash drive as FAT32 rather than as NTFS. To format the partition as FAT32, type
format fs=fat32 quick and then click ENTER.
Step 11: Type
assign and then click ENTER.
Step 12: Type
exit and then click ENTER.
Note: Leaving DISKPART program but don’t close the Command Prompt instead. We would still need it for next process.
Let us assume that the flash/USB drive is the H: drive and the Windows Installer located on drive D:\win7\.
Step 12: By default, Command Prompt’s active directory for Administrator permission is on C:\Windows\System32. We will navigate Command Prompt to set on Drive (D:) as its active directory.
D: then hit Enter, and the active directory changed to D:
Step 13: Type
cd win7\boot and hit Enter. Active directory changed to D:\win7\boot>.
Step 14: Type
bootsect /nt60 h: and hit Enter. Creating boot sector on H: drive (USB flash drive).
Step 15: Type
exit and hit Enter to close the Command Prompt. Until this step we have made a bootable USB drive sucessfully, and the flash drive is ready to be used as a boot media.
Step 16: We just need to copy the whole installation files contained from the D:\win7 drive installer to flash drive H:. Copy All the files and directories and wait until whole data is copied.
After completion the whole process use flash drive as bootable drive.