I use the "70,20,10" Strategy , I invest every moth a part of my earned money from my job and split it that way: 70% I split over the Top 10 coins. 20% I invest into coins that are not within the Top10 but have some inovation and are still well accepted for example Steem or TenX , the other 10% I use for coins that have a big risc , for example new coins and Icos . That way your profit does not depend on a single coin.