Watching price and adding creativity to your interpretations based on your memories of past price action.
Here's my $0.02 for what it's worth. Reading price action refers to watching price itself, rather than its derivatives. This means no oscillators, indicators, moving averages etc. Price action readers would annotate charts with support/resistance lines and trendlines. Candlestick patterns are an example of reading price action. Then there's the whole subject matter of "reading the tape" where one only examines time and sales data with no charts, in its purest form.
By reading price, volume and movement; you're trying to understand what is happening. "Hmmm! It looks unusual today!". I can tell you that moving speed is very important to gauge the intensity of greed and fear.
Ok I couldnt figure out if it was A - looking at a chart and seeing where the stops and limits are, and knowing probable future price action from experience, or B - seeing the way prices flash up and down in the moment, and coming to conclusions like "this thing is about to sell off" C - some mystical messageboard ideal that cannot be explained, only argued
Reading price action is having the proper experience to determine and examine, in real time, price at key levels of support and resistance while noticing and taking into consideration it's current state, whether this is a state of trend or consolidation. Anek