People can use tools or manually trace wallets of whales and see what are latest meme coins they bought. It's one of steps to filter abundant meme coins on them market and find potential x ones but this is a dependent approach and nearly completely rely on works of whales.

By using this approach, they will have to bet that whales already did their research well and carefully and did not randomly picked these meme coins because they are rich and don't care about losing money with their bets.

Generally with whatever approaches, buying meme coins is very risky, I don't recommend it. You can win with one or two but will fail with many other meme coins but risk is if you fall in love with meme coin sub ecosystem, you will sooner or later fall into bad meme coin projects.