I see a lot of really scared people talking about a subject they may not know much about.
First off investing... Invest only what you can afford to loose and if your confident invest a little bit more.
Most investments have volatility. For instance if you invest in housing at the highs. Be willing to hold through to low periods. If you lost out... you may need to hold for awhile. You will kick yourself in the ass if you sell during the lows.
If you have been holding bitcoin for a year you fucking won. Even if you didn't sell at 20 grand. If you bought in January.... you didn't.
I personally have an amount I hold and an amount I day trade with.
Ride the waves or hold. There are benefits in both but don't sell low.