It all depends on you budget, risk appetite and how you expect your investment to grow with time.
You want risky but fast returns - try new ICO (Not guarantee ICO will be successful always, so need to do more research)
You want medium returns over few months - try in coins which has over 400 pages of comments on this forum. Depending on how much you can invest decide on coins you wanna buy
Less Risky and long term holding - you need to buy coins like BTC, ETH on which market relies heavily at the moment. Check every 3 months how are your investment growing if you feel risk cash out and reinvest in best during that period.

hope it helps