Honestly, a good trader also experiences to lose their investment, all here in cryptocurrency are risky you must be smart and don't believe in any promises.
The only coins that I could suggest you that can reduce the risk of losing your investment is to choose the coin, which is mostly used by many people or choose a coin, which is on the top 10 in coinmarketcap all of them are less risk than you are investing in new ICO's or new coins because it's too risky so avoid investing in them.
Also, make sure that you can control your feeling when the price is decreasing because there are still chance that the price can recover back in the future.
Good advice mate,and thats right being a weak handed will only bring him to failure.because of volatility many traders get scared when falling and uses the Stop Loss strategy that breaks the momentum.
analyse the market
chose coins
check the exchanges
sell coins in time
the more risks you get, the more chances you have
Indeed thats why many people now are involving here in crypto because even it is more riskier but the bigger chances of gaining more