How to turn the power back on an iPhone 4 back on when the power button is broken?

MY power button broke awhile back ago, so I been using the assist touch thing. I turned the power off when I was taking a test, and now i don't know how to turn it on. I've tried to hold down the home button, press it multiple times and such.

How to turn on iPhone without power button
http://www.wikihow.com/Turn-on-an-iPhone-Without-the-Lock-Button