coin prices rise and fall in seconds, so the worst thing a coin user sells when prices go down will result in little loss.
There is a proverb ' No Risk No Gain'. How will you make good profit if there is no risk? But you should select the best Coins before investing your money there. Research about the coins and their white paper as well. You can take a look here for more details
http://scidex.co/ Looks like a good coin.
All the best!