Why did it catch your eye, it went down from 152 to 141 in a day??
One that was likely to be volatile. It started off falling, on reasonable volume, so I took a small short with a trailing stop, which went 3.8%. I didn't watch it. Could have done better if I had.
Even excellent results are frequently a prompt for a dip in a price. A long time ago I posted the quip "Participate, don't anticipate" which is ambiguous, but it means wait to see what happens then
use the move. Often a spike up is followed by an equally rapid drop - you look at the Volume as an indicator of whether the rise is likely to be sustained. You never join the rise quickly. Everyone and his dog will be waiting to short it - so you join in when that happens, and the selling pushes the price lower.
News = volatility. E.G. The oil price is twitchy. What someone actually has to pay for the stuff is marginally related to the stock market price. Bloomberg reports local oil prices, which have been over 124, way above the SM price.
The SM is a list of prices, not values.
I did wake up early this morning, "worrying about macroeconomic shocks."
Fridays can be bad.
I was thinking "I don't need this"
R4 was on, I hear Bailey's quote
I looked at $ARM - I've been holding 1k shares for a few days. It stopped rising.
Enough.
By 8:10 I'd either
sold everything, or put trailing stops under prices of the stuff that's still rising - just oil, chips and data centre names.
That will cause a market crash of course

.
But I get some time off.
I need to replace all my socks. They're all black, but none seem to quite match.
I'll have to look for where's cheap for quantity.
---
The stock market will fall...
...I don't know when.
Be ready to short it then.
You can place a sell short stop below the current price.
So if the price is 100, you put that "trip" at 97, expecting that the price will fall further. If it goes back to 100 of course, you lose.
It's a tradition among Jews who are no fools when it comes to money, to use Stock Options at times like this.
You can for instance sell a covered call.
If the price is 100, you sell someone the option to buy your stock at 110, for which they pay you a premium.
If the stock price falls you keep the shares, and the premium, because they wouldn't buy.
If it goes up, you're obliged to sell your shares at 100.
Heads you win, Tails, you don't lose.
You can also buy a PUT option. That gives you the right to sell at a specific price, so that's a hedge against a fall:
If the price drops to 80 and your Strike price is 90, you make 10 bucks a share. Otherwise, the option expires worthless but you retain value.
There are collars and squeezes, iron condors and butterflies, and a bunch of greeks, including vega, which is arabic.