How to Create Bootable USB Drive using Power ISO

Create Bootable USB Drive:

Start PowerISO (v4.8 or newer version, download here).
Insert the USB drive you intend to boot from.

Choose the menu "Tools > Create Bootable USB Drive". The "Create Bootable USB Drive" dialog will popup. If you are using Windows Vista or Windows 7 / 8 operating system, you need confirm the UAC dialog to continue.

In "Create Bootable USB Drive" dialog, click "..." button to open the iso file of Windows 7 or Windows 8.

Select the correct USB drive from the "Destination USB Drive" list if multiple USB drives are connected to thecomputer.

Choose the proper writing method. "USB-HDD" is recommended.

Click "Start" button to start creating windows 7 / 8 bootable USB drive.

If no errors occurred in the above process, you should now be all set to setup Windows 7 / 8 from USB drive!