You can also deal with bitcoin mining or other cryptocurrencies, but for mining you will certainly have to spend a lot of money. And besides bitcoin you also need monitoring stable cryptocurrencies such as etherium, litecoin, ripple, monero or other cryptocurrencies, at the moment, of course, there is nothing better than bitcoin.
Mining is not worth for try at the moment , IMO
I'm usually earn passive income from my speech on local forum since I've been trust as a speaker for bitcoin so yeah.. there is a lot way to earn bitcoin without spending too much expense