Do not sell your coin when looking at your coin soaring!
Many people have done this, the general psychological tendency of the market. Many stories share the same plot, and each time you see a coin A rising drastically, you start to sell your Coin B and immediately jump into Coin A. The psychological effect is called The FOMO is a normal fear of human psychology but is really dangerous in the Crypto market.
I agree with "don't jump into a coin when the price has jumped too high". Usually there will be a correction in price before the trend continue or changed. Btw, in trading everything will look very complicated especially what is the right time to start to buy and what is the right time to make sell order. Each person must have his own way and it differs form one to another.