Tips to find out if the selling pressure in the market has worn out

Let's take the total market (SP500, nasdaq), let's say you look at it and say: “today is a good day to invest because sell pressure has worn out”

Based on what would you tell that, beside the oscillators and indicators? What would you be looking? Personally I look at the SP500 to M2 supply chart and when I look at it I say: “this chart…a lot of money floating around and still sp500 isn't at all time highs since the 2000s in M2supply”