In this time, trading with margin is the best way to make money. But it's too risky, so you need consider carefully before join.
Well there is so many strategy to earn profit, first is hodling, if you want to earn profit, invest or buy coins at the lowest price and hodl it, no matter what happen hodl it and wait to rise, if it rise sell it to earn profit the other one is day trading, buying coins and sell it at the same time, you can earn profit fast but not as much as long term hodling.