HODL. Ethereum is full steam ahead with the big companies hopping on the Ethereum Enterprise train. Today's value will look laughable once the real useful DAPPs arrive. ZKSNARK integration will provide necessary anonymity, and proper incentivized anonymous file sharing is on the way. If they also nail a decent PoS implementation and sharding (harder said than done) the sky really is the limit.
I'm always tempted to sell when the price goes up, but in the past when I've done so I usually end up regretting it.
If you're a hodler - Ether, BTC, DASH (wish I bought more than 10 lol) and Monero are all pretty solid coins to sit on right now.
Just remember this is all really high risk and experimental stuff. I've had close personal friends with much smaller investments in crypto have major panic attacks and cause them huge amounts of stress with the price fluctuations. If you're easily stressed please stay away.
I know it's cliche but please don't invest in more than you can afford to lose (mining or buying) . Your health is the most important asset.