My opinion, Bitcoin all time saving mode is the best way. Some time when bitcoin price up then sell and when price down then buy is the best decision.
It's not as easy like that. People probably don't know what is the "bottom" or "down" is and if they just blindly follow buy when down and the price keep falling down because just merely following the "motto" without any doing research then it should not be followed. You should use any research/indicators/strategies if any possible so you can maximize your certainty of decision so you won't regret it later.
*Hold
*Sell
*Trade
Looking forward to the opinion of the experienced.
Just do DCA then if you are actually just hold it for long time.