stop dreaming about doubling your money stacked in BTC, just get knowledge about cryptocurrencies if you want to do so.
Without some really good plan, that is not going to happen unless you are extremely lucky.
Yes you cannot double your bitcoins unless you don't work hard continuously to make it possible as you cannot expect that you will be lucky every time which will help you in doubling your bitcoins in quick time and if you want to double your bitcoins with hard and honest work then it will take really long time.
In gambling it is possible, but I will not prefer this to double your bitcoin. Becasue this is not the right way to double your bitcoin. And most of the people will not succeed in this method. So you must do hard work and double your bitcoins. Trading and investing will help you to make a profit from your capital but you can not double your bitcoin.