You Do Your Own Research, you analize the coin GitHub, then watch at official website (if it's professional, has many features, wallet downloads, documentation), then you join communication channels, for example Telegram, Discord, you'll see community support and you can ask questions and try to understand if they are talking about just words or real development and things. Then you open CoinMarketCap and look at its ranking. If you think it has much more value than that reflected in ranking then you buy a stack (of course single coin value depends of its supply but with ranking you can't miss it). You HODL and maybe sooner or later people will realize what you have doing your research and will start to pump it. You then sell when you think it has reached deserved ranking and profit.