After big market sell-offs, we'll often see a bounce on the day following the biggest down day.
When analysts don't think we've seen the bottom, yet, the prudent approach is too hold off doing any buying until we see another down day.
As a rule of thumb, I try to limit buying to days where all the averages (Dow, S&P, NASDAQ) are in-the-red (i.e. down) rather than days when they're green (i.e. up).
Buy on down days, sell on up days.
That being said, if a stock you've had your eye on is in your buying levels, it never hurts to put in a position if you're Buying in Stages, but be very cautious if you decide to do any buying today.