Can you really be sure you will profit unless you have insider info?
Not at all. Trading with bitcoin requires you to follow the price flow, current events that might change the price and also a little luck.
just like gambling trading needs a little luck to have good profit in this field,because even how hard we try to analyze and make research about the said coins yet the market and investors will decide if this one grow or drop.better have enough funds before trading so when the coins bought go drop.you can hold it and try another coin for next option