1． Download ubuntu-16.04-desktop-i386.iso
2． Download Universal-USB-Installer-1.9.6.4.exe
3． Follow http://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/ and create a bootable USB flash drive (4g is enough),
4． Change the boot device order, so that the system boots from the USB
flash drive. Follow http://zh.wikihow.com/%E5%AE%89%E8%A3%85Ubuntu-Linux,
jump to step 3.
5． Detach the USB flash drive and restart computer. Done!
