it will work for the altcoins that has large capitalization,
and the other strategy trading is arbitrage, if there are different price between exchangers
unfortunately it can not happening every time.
Also i have some new one that i learned from my sensei its called "Sizing" (Averaging down) example X-COIN if you have 1BTC divide it by four so it would be 0.25BTC, then you buy X-COIN @100sats worth of 0.25BTC then x-coin dumps to 50sats, so you just need to buy again @50sats worth of 0.25BTC, then your current price is just now 75sats, so if 75sats achieved your 0.5BTC is now safe and if its back to 100sats you can earn a profit worth of 0.25BTC.
Did you get it ?