"As for turning it on, you just need to connect Pin 13 on the main connector (usually its green) to ground. That is a sense line so its very low voltage basically no current. You can even cut off the main PSU cable except for those two wires and put your power switch on that."
~ "As for turning it on"... turning on the computer PSU?
~ Connect Pin 13 and the main connector (usually green) to Ground?