Step 3: Wires, Wires Everywhere
You will be met with the daunting task of sorting through a hundred wires of different colors. The only colors we care about are Black, Red, Orange, Yellow and Green. Any other colors are superfluous and you can cut them at the circuit board.
The green wire is what tells the power supply to turn on from stand-by mode, we want to just solder it to a ground (black) wire. Put some heat shrink on this so it won't short out on anything else. This will tell the PSU to be constantly on without a computer.
Cut all of the other wires down to about a foot, and remove any zip-ties or cable organizers. You should have a forest of wires with no connectors.
The colors represent:
YELLOW = 12 Volts
RED = 5 Volts
ORANGE = 3.3 Volts
BLACK = Common Ground.
Now, theoretically, you could be done. Just hook the wires to 4 large alligator clips (one for each color set) or some other terminals. This might be handy if you're just going to be powering one thing, such as a ham radio, electric motor or lights.