There are many ways to earn moneyt in bitcoin and altcoin if you are holding them you can make a profit every price increase so the more you invest the more you can make profit but buying more altcoin is much risky because we don't know if the altcoin can be increase more its not the same as bitcoin tht can increase the value more like what the price today..
There are many ways to get and earn bitcoin you can also try affiliate marketing but you need to know how to promote an offer.. 
Or like other said trading its not easy to earn profit first you need to know the basic of buying low and sell high before you can start trading..