You have to do your own research on each project. It’s important to see how good the team is, who backs it, how much money is coming in, what value can it bring to the world and why it has the potential to explode if the market does. Once you find answers that you like for all of these questions you should invest but If not don’t. Most Altcoins will fail so it’s important you research! I personally like AAVE, NEAR, 1NCH and ADA