I guess bp is not the very best site to ask for business wisdom regarding founding a Hedge fund - Wikipedia, the free encyclopedia in particular. While bp is really a nice site to ask some basic questions regarding retail trading I'd consult a lawyer or any business club for founding a hedge fund.
Trading for others while retail trading is a completely different topic. I'd suggest to stay away from it as far as you can. Major headaches are preprogrammed:
If they lose, you get blamed and maybe serious law actions.
If they win, you are the idiot of the block.
In both cases you invested time and energy, which you probably could invest more wisely in other actions. Not only keeps it off time and energy trading for yourself. Why would you trade for others? If you can make it then trade for yourself, collect some money and invest it wisely. Giving away money or work for free is never a wise decision, because it leads people to think money is for free and it needs no work to get something. Real, lasting value however is created with work, may it be by thinking or/and working by hand.