By holding BTC you already have steady income as the value increases 
Other way is: you put a large sum of money in the bank and convert the interests to btc. But in order to make any significant income, initial sum should be really big.
I agree with you. Holding bitcoin will give us a lot of chance to earn a huge income every year. Other way is: you put a large sum of money in the bank and convert the interests to btc. But in order to make any significant income, initial sum should be really big. Otherwise, you can buy mining rig and start earning money from mining. There are many coins that can be mined and it is very profitable.
trading is also a good option for you. If you can spend time to learn about trading, it will be very good