I use the Website CoinMarketCap to keep track of my buy and sell orders, as well as look at the data from multiple exchanges in one location.
This will help me when I need to report income. It also helps me learn from my mistakes.
Either you sell to early or sell to late. Never beat yourself up. Move on from the trade and learn your lesson. Never be greedy. Greedy pigs get slaughtered.
Make sure you keep record of your research and create different journals for different hobbies and aspects of your life. If you would like, we can talk about some of my methods.