How to install Windows 7 using usb?

Yesterday I finally manage to fork out some money to buy Intel i3 530 system. So after installing all part, it time to install OS. Unfortunately, I forgot to bring my Windows 7 Installer DVD. All I had was an .iso (DVD image) file, a laptop capable only to write CD and a 4GB USB drive.

I remember there are many article out there explaining step by step guide how to install Windows 7 using an USB drive. But most of them require me to execute several command line in Command Prompt. Fortunately, there are also a few way to use simple program.

1. UNetbootin (Please visit this link)
2. Microsoft's Official Tools (download)
3. UltraIso

I pick the 3rd option because I already have the software and here the steps.

What you need:

• 4Gb USB drive
• UltraIso (trial) download here
  
• Windows 7 Installer images files

If you don't have installer images file, you can create one using UltraIso.

The steps:

1. Start UltraISO as administrator
2. "Burn" the iso image to the USB stick by following these steps
   - Open the image of Windows 7 with UltraISO
   - Under BOOTABLE tab choose WRITE DISK IMAGE
   - Choose your USB stick under "Disk Drive"
   - Choose a method (It's recommended to use USB-HDD+)
   - Tick Verify
   - Press Write
3. After finish "Burning", restart you computer.
   
4. Make sure to change your BOOT order in BIOS to boot from your USB drive first