How to double your money?
You want an idea to double or maybe triple your money, I suggest you to invest in cryptocoin and not any cryptocoin. Invest in Lisk coin. Lisk is a coin with the bright future. If you google about Lisk, you will see that you can earn money if you invest on time. Just buy Lisk and wait for your money to raise.
Why?? you haven't given any reason. 5 lines of nothing.
I just gave you an idea where to invest. I did invest in lisk and I doubled my BTC.