Shorting tesla might not seem a bad plan for about a decade now, the market can remain illogical longer than the premiums you pay on the short position.
Well you can also have "know how" from other things, for example years ago I was following a lot of PC hardware news and for me it was sure as fuck that both AMD and Nvidia will only increase for a while, Ryzen was starting to go strong and Intel was not putting up competition, and the then crypto market nicely transitioned into AI for keeping demand for Nvidia products high af.
Anyone who knew someone from the boeing factories or had knowledge of what went on in that company likely should have known to short the shit out of the boeing stock the moment the first 787 Max went down.
Really the stock market involves a lot of paying attention to stuff and then trying to to bet on the more likely stuff, it's never a guarantee is it.
Right now I am mostly paying attention to the car market, there I would say shorting US car manufacturers is a decent bet, Nissan if the stock is still low is a decent investment target, I don't think they will go under and they have some nice cars at good prices.
Stellantis went through a bit of turbulence, but they are coming out with some good stuff now, so they could see some upswing.
But really I haven't even looked at the stock prices so this might be all stupid shit.
If you don't want to gamble just invest in ETFs every month and you will be fine.
No I don't proof read, I am an idiot who sucks at his job