Before looking at potential crypto currencies and starting trading, you must find out which strategy you want to pursue. Everyone has their own tactics but they are generally included in the categories:
Long term - You just want to buy a few different coins and save them as a long-term investment. This is the simplest trading strategy and usually involves the least amount of risk.
Investors - You have a risk tolerance that is slightly higher than the long-term hodler. There may be coins that you hold for a while.
Daytrader - The most sophisticated and most risky cryptocurrency trading strategy. You focus primarily on technical analysis to trade volatile changes in the market.

and most importantly, you have to find out what problems are solved by the coin development team, why the team is qualified to make it, and what is the purpose of the coin in the overall ecosystem.