STOP CLOCK MECHANIC???

[mtbabo]

Please clarify the following.
What is the proper mechanic for stopping the clock when the ball goes out of bounds on your line? I have read that you have to put up your hand first to stop the clock and then point direction. I have also been told that we are not supposed to put our hand up and just point direction. I need some hard evidence to prove what is the correct way not what each official would like to do. Was it discussed at the NCAA clinics this year? If possible please quote references or links with references.
Thank you