YOu just need to buy an altcoins with a very low price then sell it on a right tiome or high price .. If the price goes down buy an altcoin again to have a profit the wait .
to me by taking right decision in a right time is a tood of successful trading, you must study about the project or field where you are going to invest your money, you must also be very patient and broad minded and having decision power hope the suggestion will help you in successful trading.