Just don't get swept up by the hype and don't be swayed by FUD, that's the two of the most important things to avoid when trading Bitcoin or any crypto and most importantly, aside from those two, don't sell based on your emotion. Once you've entered a position, you should exit that position based on whichever strategy you have in place. If you hold a crypto (ex. BTC, ETH or LTC) and these crypto falls in value, you must evaluate the situation first before selling your holdings and yes, journaling really helps.