If this dips below $220 that's a good entry point. If it goes below $200 then you leverage every dollar you can because that will be very easy money for a long position.
Those who are short should exit thier positions soon while they can still make good money. Once this market correction ends, the broader market will claw back because fundamentals here in the United States are still good. This correction is due the ending of QE and once we turn that corner there isn't any other major negative news to weight down on stocks.