If you are just trading, then it is unlikely. You can double the capital only by participating in illegal schemes such as a pump and dump. There is a second way, it is trading with leverage, but here with a 99% probability, you will lose all the money, because only professionals should use this tool.
Trading income can be doubled depending on our skills, how much knowledge we do have about trading and how much capital we are referring to it. If you are beginner in trading, it is really unlikely to happen because you are still afraid in taking risk, more on you are just conservative type of trading wherein you are happy already with a 3-5% income, then, as time is passing by you are already learning to take risk too.