First before i bought my first bitcoin, i first of all build a good understand of the market and how bitcoin volatility works, and also learned about the effect of external forces in determining the price of Bitcoin such as exchange crisis and other governmental policies that can have short time effect on bitcoin.
You did good learning but it is not enough. Purely reading and learning can not help you understand it entirely. You must be in the market to digest such knowledge and feel about it. With your experience, you will know such knowledge is right or wrong.
Secondly i have learned never to panic during any crisis time or when the bitcoin price drop significantly because in the near future it will increase in value again, and also to hold an amount i can afford to look away from for a long time.
Practicing to control your emotion, psychology and avoid being panic with news is good practice. If you experience the market enough, you will be able to exit when market starts to fall and can buy it later to increase your coin.
If you can not do it, holding is best.
Remind that it is useful strategy for Bitcoin, not for altcoins that have more sensitivity with news and uncertainty of their survival.