If you're in it only to try to make some money by buying and selling at the right time, the standard rule of "only invest what you can afford to lose" is highly recommended.
Others would argue that is everyone's agenda, but I can easily point to fanatical miners and enthusiasts that have different motives and a longer history with cryptos. Do a web search for Silk Road, for example.
Depending on the coin, sometimes changing the algorithm and firing all of the miners makes sense, you'll see a lot of differening opinions on that one too.
It's all here for you to try to figure out, or at least kill some time while time is killing you