Depends how aggressive you want to be with it but I would spilt it up into 5 bits then pick 2 coins from the top 25, another 2 from the top 25-200, and then one coin outside that for a pure gamble. That way you diversify and at the same time are in some solid coins too.
Basically dude I have the same question (because $50 is all I got haha) and I've been asking around facebook and telegram... most people are saying the same thing.
also this video on youtube offers a guide about what you're asking.
https://www.youtube.com/watch?v=wX_9aRlLg10 I watched it recently and thought it was nice.
GOOD LUCK MY FRIEND!