1. Connect the OTG usb cable to usb hub and then connect usb keyboard and usb thumb drive (The Windows 10 have been preload into the usb thumb drive (By using Windows USB/DVD Download tools))
2. Press “Esc” or “Del” to enter the BIOS
2a. Please check you are using the latest BIOS or not (http://www.pipo.cn/En/index.php?m=About&a=gujian_show&id=240
3. Change the USB thumb drive to the first boot device
4. Follow the installation wizards to install the Windows 10 Preview
5. Force reboot the tablet, I did serveral time during the installation. (Optional)
6. Download and install all W4 driver one on one via the device manager
Download the PIPO W4 driver (http://pan.baidu.com/s/1c0bAzdA) or (http://www.pipo.cn/En/index.php?m=Product&a=show4&type=2&id=352)
7. After install the WiFi driver, you should run the Windows update asap.
8. You should be able to use the Windows 10 now
Reference:
http://www.microsoft.com/en-us/download/windows-usb-dvd-download-tool