my strategy to deal with the price volatility is to estimate a reasonable value that can be expected in the long-term and to invest under that and sell over that - ignoring the volatility in between.
Each crypto-app has a market cap just like a stock with which to judge whether its over or under valued. This is a good site to see the market caps for all the cryptos: coinmarketcap.com
I get the argument that one should avoid investing due to the volatility... but that's only if you're going in to gamble starting at a random price hoping for a random increase. If you had valued bitcoin at $100, or even just $10 a few years ago you would have made a healthy return - ignoring the meteoric rise to $10,000 (and I still think that's under valued)