Sometimes you can get a great short even when the market is already down a lot.
You wait for all the signals to line up.
If AD is rising... then wait it out -- you'll eventually see the synchronicty in the form of a TL or double top/bottom... alerting you to the edges (and hence, where to place a stop).
Midday is nearly always a difficulty choppy time.
The eventual plummet - which was obvious due to extreme AD reading, resolved just after 2 pm and gave you everything you were looking for fast and easy. Did you stay out until then?
Do you have the patience to wait for the set up?