Some people here thinks that it's possible but well, this task is not so easy. For example, if you purchased bitcoin at 900$ and tomorrow you see that price is 800$ now, waiting still some days and weeks and you see that price is stable at 800-850, what are you going to do? If you'll sell bitcoins, you will lost profit. So this makes fixed income with btc trading impossible. Better to trade daily but in some situation, wait for more than one month.
well to put simply, only someone who has no idea what trading is and wants to make money does that. in other words he is gambling not trading.
when you trade, you open positions, you think about all the possibilities, if you think price is going down then you don't buy, you wait to buy. an in situations like price going down from $900 to $800 (which are extremely rare by the way) you don't just go to sleep wishing it won't happen,you place some stop loss orders so you don't lose $100 and then buy back at the bottom to not miss the come back.
and if you can't do any of these then you shouldn't be trading at all.