<prompt> Human: i have 400 dollars to spare and i would like to do something to double it? Any suggestions reddit? Im sure i would probably need more to invest in stocks and as of right now i dont think i could save up till 2000 or anything like that. I am debt free obviously. If i have to learn a new skill i will. Helpful comment would be appreciated. Not looking to make some quick cash.  <response>: You can double your investment by buying and holding index funds for several years. But it sounds like you want a short term win. Dont think like that. Start saving a good portion of everything you earn and youll be surprised how quickly you can build a nice nest egg. 