timing the bottom of a panic is pretty hard to do. Sometimes you will see some huge volume come in and stop the fall, I will always buy when this happens. But other times it falls to a low price and then turns up so fast that there is no time to react, so I simply buy whenever I see obvious panic selling below a base and I dont even try to time the bottom... However If I see clear support come in and maybe some stuffing, then I quickly add to my position.