I have simple strategies.

1. When Bitcoin rise and ETH/USD price is not moving for a day, then it's time to buy ETH

2. When ETH/ETC price is below 0.08, it's time to buy ETC, it's always at least 10% of ETH

3. When ETH and ETC keep rising and REP is not moving or falling, it's time to buy REP, it always follow ETH movement but delay.

4. If Steem is rising and BTS is not, buy BTS it follows Steem movement and vise-versa.

Disclaimer: Not an expect just my personal observation.