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1.
When you stay up to 12:00 PM in the next day.

How to preform a 'till the clock says FM:

1. Wake up before 12:00 PM (noon)
2. Consume energy drink of choice. (You will want to do this step. Trust me.)
3. Pull off an all-nighter
4. Stay up 'till 12:00 PM in the next day where sleep deprivation will most likely change PM on clocks to FM and FM on radios to PM.
I pulled off a 'till the clock says FM. It was brutal.

I was super tired when I tried to do the 'till the clock says FM.

I preformed the 'till the clock says FM +12 hours. AM stays AM on clocks.
by James1011R April 02, 2011