I often wonder why investors can lose sleep over trading. I buy a stock, like TSLA or any of the magnificient seven stocks, go to sleep and more often than not, I see then turned green. How do I achieve this you might ask. Simply said, I do not buy a stock without doing my due diligence. When the stock prive has dipped to its support levels or too low for comfort, I would just buy some and pick more when it dips further. Then I go to sleep peacefully as I believe I have picked the shares up at the level I had expected. So happy to see them turn green and if trading is still on or in the post market, I would sell off for profits. I do not believe in holding stocks for the long term except for some of the bluest of chips, like Apple, AAPL. 

Hence, dont loose sleep over your trades. Buy at levels you are comfortable with after doing your due diligence. Best strategy is to pick up when prices hit rock bottom and sell off when it curls up. For Tesla and Apple recently, I did not loose any sleep but made handsome profits scalping off prives at the high.