A good way to minimize the risks is not invest real money (or invest a little amount).
With some efforts you can earn bitcoin from faucets, forum signature campaigns, glambling (not recomended), trades, etc...
After achieve a good bitcoins amount you could invest It. If you lose all, you don't lose your money.
If a person will not invest real money then he will not take any benefit as if someone will start with nothing then he will not earn faster and he will then feel too late and slow and will regret which I am feeling. But if someone will want a faster profit then he have to invest some real money.