first you need to get knowledge of the past and present of any coin you wants to trade. Keep an eye on the market as well as other coins. Whales will do the rest of the things 
What do you whales will do the rest of thing,? Can you explain more clearly? Thank youthe whales will come to the market and analyze each of coins and if they think that they can join in the buy and sell order then they will do something. maybe they will pump the price or dump the price or make a big wall for the price so the price cannot go to go up or down too far. with the big balance that they have, they can do everything that they want. and we can follow their step in the market then we can also make a profit like they did and if somehow they dump, we could know the sign.