Try a x2 on any gambling game, preferably on a no house-edge lottery like Peerbet. And if you lose everything, well, anyway there's no safe way to increase your money x) This would be too easy
This is how I doing it, though never sucessfull so far If I keep doubling few times (I know, greedy)
I assume you follow the good and smart way to handle the bitcoin transaction according to the financial market money flow, you will make it, it is not greedy, it is your hope that bitcoin will have good marginal value in near future, there is nothing wrong in that, however keep watching the money exchange transactions, you will have your best luck !