It doesn't matter if you are a scalper or a day trader, you need to understand one of the most important rules of successful trading: you can only earn on active coins that have market interest. You can identify such a coin by 3 criteria:
1. Increased relative volume. The key word here is 'relative'. This means the daily volume should increase by 3 times or more compared to the volume at which the coin is usually traded. Typically, an increase in volume is accompanied by a strong rise or fall in price. Such coins are easy to find in any scanner or even on the exchange itself by sorting coins by growth and decline.
2. Increased volatility. This indicator is more complicated, as it heavily depends on the liquidity of the coin. For example, for $ETH a volatility of 0.5 on the 5M timeframe will be high. For a low-liquid coin - low. In altcoins, you should aim for a volatility of about 1% on the 5-minute timeframe.
3. Correlation with Bitcoin. This indicator tells us how much the movement of the coin depends on the movement of BTC. The lower the correlation, the better. Ideally, it should be negative.
If you are not yet able to determine volatility and correlation 'by eye', I recommend using the LazyScalp Board indicator which can be found in the TradingView scanner. It is located in the lower right corner of the screen.

In the photo, the coin $LISTA On the indicator, we see that the volatility of the coin is 1.56, and the correlation is -0.05 on the five-minute timeframe. This indicates that there is interest in the coin from the market, and it should be added to the watchlist. However, this coin still has a very small traded daily volume - only 24 million. Therefore, it is not suitable for trading at the moment.
It is important to understand that the lower the relative daily volume of a coin, the cheaper it is for the market maker to manipulate it. This means it is easier for them to create a so-called 'squeeze' in either direction and trigger your stops. Specifically, I would not touch the coin Lista until the daily volume grows to at least 100 million. I generally do not recommend trading coins with a daily volume of less than 100 million.

For quick searching of volatile coins, you can use various scanners, for example, Scalper Station.