I recommend to HOLD and buy and sell both! Like if you have 2 BTC, then keep holding 1 BTC for a long time. And by other btc, You can sell that at a higher price and buy again when the price goes to down. This is the best strategy for you, this is my recommendation. Good Luck.
My opinion is quite the same. It is good to HODL the Bitcoin you have bought whether cheap or expensive for the reason that it will eventually have a much expensive price after some time, and when time comes then sell it. It is nonsense for me if a person will just keep on holding and not selling his/her Bitcoin.