What I do and had been working, is to play with the average value of my investments, to stay with 5 or 6 coins only, and put money on them when the price decrease, so if at the beginning I bougth the coin at 4, and now is at 2, I do more investment to have the average value on 3 or less, so at 3 I will have profits instead of the beginning at 4. This means that if the price is falling you will have to keep buying the dip, cause if that is a really good coin it will come back at any time. That worked for me for NANO and other coins.