Honestly, I don't deal with Twitter campaigns much, as I respect my followers and don't want to inundate them with spammy links from ICO's or crypto companies that I personally do not endorse. And honestly, you're not going to make a living doing Twitter or Facebook bounties here. We're only talking a few bucks a pop.

Signature campaigns, however, are a great way to earn. Just don't be a shitposter, and look for some high-paying campaigns. Make sure that your post quality is up to par with other participants, set a goal for yourself, and try to rank up. You will generally earn more as you reach higher ranks, and unfortunately, you're not going to make a lot as a Jr. Member. High-paying signature campaigns for Bitcoin are pretty rare here, but you will find a lot of new signature campaigns that offer a small payment in Bitcoin with an additional payment for their altcoin. Some of these can end up extremely lucrative, especially if the company of the signature you're wearing actually makes it to ICO and provides a valid and legitimate value of service for their coin... But again, you're only looking at making approximately $50-300/month from a signature campaign (with a Jr. Member/Member rank), and I don't think you'll be able to survive off that. As a Sr. Member, Hero Member, and Legendary Member, you can make upwards of $1000+ per month from wearing their sig.

Oh, and don't discount Steemit. My friend is an article writer, and he does posts here and there for SEO and he's averaging about $40-50 per post at the moment. If you understand social dynamics and how to engage with your audience, Steemit can be an amazing platform. Be creative and engaging