Aside from knowing what cryptocurrencies to buy, one should also consider understanding when to buy. Of course the general rule is to buy when you feel like it's the lowest price of the crypto for this season but it will be difficult. There altcoins that never rise up again when their prices continuously decrease until they get delisted in exchangers. It is important to at least research more about the trend in which the prices and trade volume are going and understand the risks it bears.