Actually, yes. Social media is the way to promote business these days. Really: There are people who do more social media than actual work, and are successful because of it. There are some excellent guides online.
Having a blog is great, but also a Facebook, perhaps Instagram, Tumblr, or even a YouTube channel, and more, will all be helpful.
There are a few tarot readers on YouTube who do some broad periodic readings, and use it to promote their services; one person in particular I have watched will do reading videos for a person -- and he uses a nick name they both agree upon to help preserve privacy -- as well as reviews of different decks, and lessons on divination using tarot.
Another I know of will make a post on Reddit with her weekly readings, though I'm not so sure how well that's received.