Long-term investment is such a  very risky decision to do. In order for you to be successful on it, you need to analyze and read a lot about each coin / token you want to invest witjh, in order to understand what kind of project it is and whether it will be in demand in the future. But also long-term investments are most profitable. Honestly, I am also  a long-term investor only by 90 percent, the remaining 10 are for short time trading (which I can also make a profit).