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.
Faucet is a safe method to earn bitcoin but also ate a lot of your time for me this is not an option because time is important you can do more productive to earn more and big. To earn big you will always need to risk or invest your money if you want good income choose to invest on investment site and trading you can earn good amount if you know the mechanics
With all sorts of bitcoin related activities risk come along with it. The goodness with it is the profiting based on the risk one takes. As stated faucets were the only risk free earning source but the time spend on it is simply waste, because won't be benefitted with a better earning. Have some investment and make yourself active into trading or gambling.