actually, selling your coins when the price falls down and buying back when the price recovers but the most important thing is how do you know when the price start increasing again? So, the best way is researching carefully before buying to get success
That is the most important question when it comes to trading "how do you know when the price start increasing again", isnt't it?
I personally trade almost everything like cryptos, forex, stock etc and I can tell you that not like other markets cryptos are really good for long term holding.