putting Arduino R3 into Dfu-mode without any other Arduino device

Hello, I have Arduino R3 and I would like to update the firmware in order to use it as a HID device. i have found the instructions for updating the firmware for R1 by itself but couldnt find any for R3, as its circuit design is different from R1's. I will really appriciate if somebody could help me out for that.

Sorry I forgot to mention, it is Arduino "Uno" R3.